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 A007644 M5307 #30 Feb 16 2020 01:17:06 %S A007644 53,71,103,107,109,149,151,157,163,167,173,181,191,193,197,199,223, %T A007644 233,263,271,277,281,293,311,313,317,331,347,349,353,359,367,373,379, %U A007644 383,389,397,401,409,419,421,433,439,443,449,457,461,463,467,479,487,491 %N A007644 Primes not of form | 3^a +- 2^b | where a, b are nonnegative integers. %C A007644 Contains all primes congruent to 53, 77 or 103 modulo 120. - _Jianing Song_, Feb 15 2020 %D A007644 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %H A007644 H. Gauchman and I. Rosenholtz (Proposers), R. Martin (Solver), <a href="https://www.jstor.org/stable/2691457">Difference of prime powers, Problem 1404</a>, Math. Mag., 65 (No. 4, 1992), 265; <a href="https://www.jstor.org/stable/2690747">Solution</a>, Math. Mag., 66 (No. 4, 1993), 269. %e A007644 127 = 2^7 - 3^0, so 127 is not a member. %e A007644 257 = 3^0 + 2^8, so 257 is not a member. %Y A007644 Cf. A007643, A004051, A103146. %K A007644 nonn %O A007644 1,1 %A A007644 _N. J. A. Sloane_, _Mira Bernstein_, _Robert G. Wilson v_ %E A007644 Minor edits by _N. J. A. Sloane_, Jun 27 2010 %E A007644 More terms from _Jon E. Schoenfield_, Jun 30 2010