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 A070969 #22 Mar 28 2023 18:59:59 %S A070969 5,9,33,513,131073,8589934593,36893488147419103233, %T A070969 680564733841876926926749214863536422913, %U A070969 231584178474632390847141970017375815706539969331281128078915168015826259279873 %N A070969 a(n) = 2^(2^n + 1) + 1. %H A070969 Vincenzo Librandi, <a href="/A070969/b070969.txt">Table of n, a(n) for n = 0..13</a> %e A070969 a(0)=5 because 2^(2^0 + 1) + 1 = 2^(1 + 1) + 1 = 2^2 + 1 = 4 + 1 = 5. %t A070969 2^(2^Range[0, 9] + 1) + 1 (* _Vladimir Joseph Stephan Orlovsky_, Jun 22 2011 *) %o A070969 (Magma) [(2^((2^n)+1))+1: n in [0..8]]; // _Vincenzo Librandi_, Jun 20 2011 %o A070969 (PARI) a(n)=1<<(2^n+1)+1 \\ _Charles R Greathouse IV_, Jul 30 2011 %o A070969 (Maxima) A070969(n):=(2^(2^n+1))+1$ makelist(A070969(n),n,0,10); /* _Martin Ettl_, Dec 10 2012 */ %Y A070969 Cf. A000215, A006485, A077585. %K A070969 nonn %O A070969 0,1 %A A070969 Anonymous, May 17 2002 %E A070969 Edited by _Robert G. Wilson v_, May 20 2002