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 A178537 #22 Jun 27 2024 22:18:16 %S A178537 1,3,21,119,329,339,1533,2031,67857,68491,1472837,7105255,20933977, %T A178537 91061443,344607757,137379807,942687265,22093239035,115763405909, %U A178537 23058549975,581930881897,8126485230643,18131637168157,69459897210831,12202023051569,1785877136688747,4676672234192229,4337085752026823,51543753266508665,431102794881380259,338696479165696557 %N A178537 a(n) = (2n+1)^(2n+1) mod 2^(2n+1). %H A178537 Robert G. Wilson v, <a href="/A178537/b178537.txt">Table of n, a(n) for n = 0..1000</a> %F A178537 a(n) = A000312(2n+1) mod A000079(2n+1). %p A178537 A178537 := proc(n) %p A178537 local o ; %p A178537 o := 2*n+1 ; %p A178537 modp(o &^ o,2^o) ; %p A178537 end proc: # _R. J. Mathar_, Oct 10 2014 %t A178537 f[n_] := PowerMod[2n +1, 2n +1, 2^(2n +1)]; Array[f, 25, 0] (* _Robert G. Wilson v_, Dec 13 2016*) %o A178537 (PARI) a(n)=lift(Mod(2*n+1,2^(2*n+1))^(2*n+1)) \\ _Charles R Greathouse IV_, Dec 13 2016 %Y A178537 Cf. A000079, A000312. %K A178537 nonn %O A178537 0,2 %A A178537 _Juri-Stepan Gerasimov_, Dec 24 2010