This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A133636 #19 Jan 30 2025 15:47:47 %S A133636 9,27,49,63,77,81,91,99,117,119,121,133,143,153,161,169,171,187,189, %T A133636 203,207,209,217,221,243,247,253,259,261,279,287,289,297,299,301,319, %U A133636 323,329,333,341,343,351,361,369,371,377,387,391,403,407,413,423,427,437 %N A133636 Nonprime numbers k such that binomial(k+p,k) mod k = 1, where p=6. %C A133636 Also composite n such that binomial(7*n,7)== n (mod n^2). - _Gary Detlefs_, Sep 24 2013 %H A133636 Harvey P. Dale, <a href="/A133636/b133636.txt">Table of n, a(n) for n = 1..1000</a> %t A133636 Select[Range[500],CompositeQ[#]&&Mod[Binomial[#+6,#],#]==1&] (* _Harvey P. Dale_, Jan 30 2025 *) %o A133636 (PARI) isok(n) = ! isprime(n) && ((binomial(n+6, n) % n) == 1); \\ _Michel Marcus_, Sep 25 2013 %o A133636 (PARI) isok(n) = ! isprime(n) && ((binomial(7*n, 7) % n^2) == n); \\ _Michel Marcus_, Sep 25 2013 %Y A133636 Cf. A000040, A133620-A133625, A133630, A038509, A133634-A133636. %Y A133636 Cf. A133876, A133886, A133880, A133890, A133900, A133910. %K A133636 nonn %O A133636 1,1 %A A133636 _Hieronymus Fischer_, Sep 30 2007