cp's OEIS Frontend

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.

A007521 Primes of the form 8k + 5.

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%I A007521 M3828 #61 Sep 08 2022 08:44:35
%S A007521 5,13,29,37,53,61,101,109,149,157,173,181,197,229,269,277,293,317,349,
%T A007521 373,389,397,421,461,509,541,557,613,653,661,677,701,709,733,757,773,
%U A007521 797,821,829,853,877,941,997,1013,1021,1061,1069,1093,1109,1117,1181,1213
%N A007521 Primes of the form 8k + 5.
%C A007521 Primes of the form 4x^2 - 4xy + 5y^2 with x and y nonnegative. - _T. D. Noe_, May 08 2005
%C A007521 Prime numbers 2k+1 with k even such that 2k+1 | 2^k+1. - _Hilko Koning_, Jan 21 2022
%D A007521 Milton Abramowitz and Irene A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards Applied Math. Series 55, 1964 (and various reprintings), p. 870.
%D A007521 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H A007521 Ray Chandler, <a href="/A007521/b007521.txt">Table of n, a(n) for n = 1..10000</a> (first 1000 terms from T. D. Noe)
%H A007521 Milton Abramowitz and Irene A. Stegun, eds., <a href="http://www.convertit.com/Go/ConvertIt/Reference/AMS55.ASP">Handbook of Mathematical Functions</a>, National Bureau of Standards, Applied Math. Series 55, Tenth Printing, 1972 [alternative scanned copy].
%t A007521 Select[8Range[0, 160] + 5, PrimeQ]  (* _Harvey P. Dale_, Apr 22 2011 *)
%o A007521 (PARI) list(lim)=select(n->n%8==5,primes(primepi(lim))) \\ _Charles R Greathouse IV_, Jul 25 2011
%o A007521 (Haskell)
%o A007521 a007521 n = a007521_list !! (n-1)
%o A007521 a007521_list = filter ((== 1). a010051) a004770_list
%o A007521 -- _Reinhard Zumkeller_, Aug 17 2012
%o A007521 (Magma) [p: p in PrimesUpTo(2000) | p mod 8 eq 5]; // _Vincenzo Librandi_, Jun 26 2014
%o A007521 (Python)
%o A007521 from sympy import isprime
%o A007521 print(list(filter(isprime, range(5, 1214, 8)))) # _Michael S. Branicky_, May 13 2021
%Y A007521 Cf. A010051.
%Y A007521 Subsequence of A004770; see also A045323.
%K A007521 nonn,easy,nice
%O A007521 1,1
%A A007521 _N. J. A. Sloane_, _Robert G. Wilson v_