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 A002255 M0826 N0315 #33 Jul 29 2023 23:14:53 %S A002255 1,2,3,7,10,13,25,26,46,60,87,90,95,145,160,195,216,308,415,902,1128, %T A002255 3307,6748,7747,8348,11193,27243,44033,47665,103542,141517,280908, %U A002255 402267,405615,745926,1069956,1083900,1457977,1507881,1755887 %N A002255 Numbers k such that 7*4^k + 1 is prime. %D A002255 H. Riesel, Prime numbers and computer methods for factorization, in Progress in Mathematics, Vol. 57, Birkhauser, Boston, 1985, Chap. 4, see pp. 381-384. %D A002255 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence). %D A002255 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %H A002255 Ray Ballinger, <a href="http://www.prothsearch.com/index.html">Proth Search Page</a>. %H A002255 C. K. Caldwell, <a href="http://www.utm.edu/research/primes/">The Prime Pages</a>. %H A002255 R. K. Guy, <a href="/A005165/a005165.pdf">The strong law of small numbers</a>. Amer. Math. Monthly 95 (1988), no. 8, 697-712. [Annotated scanned copy] %H A002255 R. M. Robinson, <a href="https://doi.org/10.1090/S0002-9939-1958-0096614-7">A report on primes of the form k.2^n+1 and on factors of Fermat numbers</a>, Proc. Amer. Math. Soc., 9 (1958), 673-681. %H A002255 <a href="/index/Pri#riesel">Index entries for sequences of n such that k*2^n-1 (or k*2^n+1) is prime</a> %o A002255 (PARI) is(n)=ispseudoprime(7*4^n+1) \\ _Charles R Greathouse IV_, Jun 06 2017 %Y A002255 See A032353 (which is the main entry for this sequence) for more terms. %K A002255 hard,nonn %O A002255 1,2 %A A002255 _N. J. A. Sloane_ %E A002255 More terms (from A032353) added by _Joerg Arndt_, Apr 07 2013