First-order logic formula(prime numbers)
$begingroup$
How to write into a first-order logic formula:
1) $m$ is prime number, which consists in $[sqrt{n},n]$
2) $n$ is number of second power of prime number.
$textbf{My work:}$
Prime number can be written like: $prime(x) = 1<x, wedge, forall u, v (x = u cdot v rightarrow u = 1 vee v =1)$.
2) I think that in this case it can be written like $n = 1<n, wedge, forall u, v (n = ucdot u cdot v cdot v rightarrow u = 1 vee v =1)$, but Im not sure
1) Here I have no idea, how to do it...
logic first-order-logic
$endgroup$
add a comment |
$begingroup$
How to write into a first-order logic formula:
1) $m$ is prime number, which consists in $[sqrt{n},n]$
2) $n$ is number of second power of prime number.
$textbf{My work:}$
Prime number can be written like: $prime(x) = 1<x, wedge, forall u, v (x = u cdot v rightarrow u = 1 vee v =1)$.
2) I think that in this case it can be written like $n = 1<n, wedge, forall u, v (n = ucdot u cdot v cdot v rightarrow u = 1 vee v =1)$, but Im not sure
1) Here I have no idea, how to do it...
logic first-order-logic
$endgroup$
add a comment |
$begingroup$
How to write into a first-order logic formula:
1) $m$ is prime number, which consists in $[sqrt{n},n]$
2) $n$ is number of second power of prime number.
$textbf{My work:}$
Prime number can be written like: $prime(x) = 1<x, wedge, forall u, v (x = u cdot v rightarrow u = 1 vee v =1)$.
2) I think that in this case it can be written like $n = 1<n, wedge, forall u, v (n = ucdot u cdot v cdot v rightarrow u = 1 vee v =1)$, but Im not sure
1) Here I have no idea, how to do it...
logic first-order-logic
$endgroup$
How to write into a first-order logic formula:
1) $m$ is prime number, which consists in $[sqrt{n},n]$
2) $n$ is number of second power of prime number.
$textbf{My work:}$
Prime number can be written like: $prime(x) = 1<x, wedge, forall u, v (x = u cdot v rightarrow u = 1 vee v =1)$.
2) I think that in this case it can be written like $n = 1<n, wedge, forall u, v (n = ucdot u cdot v cdot v rightarrow u = 1 vee v =1)$, but Im not sure
1) Here I have no idea, how to do it...
logic first-order-logic
logic first-order-logic
asked Dec 10 '18 at 20:20
Aleksandra Aleksandra
545
545
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
$begingroup$
Hints:
For (1), $m in [sqrt{n}, n]$ iff $n le m^2 le n^2$.
For (2), it is much simpler to use an existential quantifier to express the property that there exists a prime, $p$, such that $n = p^2$. Your suggestion involves a neat idea but it doesn't quite work, e.g., your predicate holds if $n$ is not a square, because then there are no $u$ and $v$ such that $n = u^2v^2$.
$endgroup$
add a comment |
Your Answer
StackExchange.ifUsing("editor", function () {
return StackExchange.using("mathjaxEditing", function () {
StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
});
});
}, "mathjax-editing");
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "69"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3034417%2ffirst-order-logic-formulaprime-numbers%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
Hints:
For (1), $m in [sqrt{n}, n]$ iff $n le m^2 le n^2$.
For (2), it is much simpler to use an existential quantifier to express the property that there exists a prime, $p$, such that $n = p^2$. Your suggestion involves a neat idea but it doesn't quite work, e.g., your predicate holds if $n$ is not a square, because then there are no $u$ and $v$ such that $n = u^2v^2$.
$endgroup$
add a comment |
$begingroup$
Hints:
For (1), $m in [sqrt{n}, n]$ iff $n le m^2 le n^2$.
For (2), it is much simpler to use an existential quantifier to express the property that there exists a prime, $p$, such that $n = p^2$. Your suggestion involves a neat idea but it doesn't quite work, e.g., your predicate holds if $n$ is not a square, because then there are no $u$ and $v$ such that $n = u^2v^2$.
$endgroup$
add a comment |
$begingroup$
Hints:
For (1), $m in [sqrt{n}, n]$ iff $n le m^2 le n^2$.
For (2), it is much simpler to use an existential quantifier to express the property that there exists a prime, $p$, such that $n = p^2$. Your suggestion involves a neat idea but it doesn't quite work, e.g., your predicate holds if $n$ is not a square, because then there are no $u$ and $v$ such that $n = u^2v^2$.
$endgroup$
Hints:
For (1), $m in [sqrt{n}, n]$ iff $n le m^2 le n^2$.
For (2), it is much simpler to use an existential quantifier to express the property that there exists a prime, $p$, such that $n = p^2$. Your suggestion involves a neat idea but it doesn't quite work, e.g., your predicate holds if $n$ is not a square, because then there are no $u$ and $v$ such that $n = u^2v^2$.
answered Dec 10 '18 at 20:39
Rob ArthanRob Arthan
29.3k42966
29.3k42966
add a comment |
add a comment |
Thanks for contributing an answer to Mathematics Stack Exchange!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
Use MathJax to format equations. MathJax reference.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3034417%2ffirst-order-logic-formulaprime-numbers%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown