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 A249305 #23 Jun 28 2024 17:36:38 %S A249305 2,89,149,151,383,409,443 %N A249305 Primes p such that 2^p - p^2 is not squarefree. %C A249305 Sequence is infinite, containing all primes congruent to 2, 4, 89, or 115 mod 147. - _Charles R Greathouse IV_, Oct 28 2014 %C A249305 997 is also a term in this sequence. - _Kevin P. Thompson_, Jun 13 2022 %F A249305 a(n) < (21 + e)*n log n for any e > 0 and all large enough n. - _Charles R Greathouse IV_, Oct 28 2014 %e A249305 2 is in this sequence because 2 is prime and 2^2 - 2^2 = 0 is not squarefree. %o A249305 (Magma) [n: n in [3..269] | IsPrime(n) and not IsSquarefree(2^n - n^2)]; %o A249305 (PARI) is(n)=isprime(n) && !issquarefree(2^n-n^2) \\ _Charles R Greathouse IV_, Oct 28 2014 %Y A249305 Cf. A005117, A024012. %K A249305 nonn,more %O A249305 1,1 %A A249305 _Juri-Stepan Gerasimov_, Oct 25 2014 %E A249305 a(5)-a(6) from _Charles R Greathouse IV_, Oct 28 2014 %E A249305 a(7) from _Kevin P. Thompson_, Jun 13 2022