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 A225578 #17 Sep 25 2024 09:54:57
%S A225578 1,5,354,67171,14914341925,13421957361110,28101527071305611528,
%T A225578 60182438244917445266889,525344775209112229247070397995,
%U A225578 51296981152155330485450049059398345004638,319099356359853147544285512855368258519442575
%N A225578 Sum of first (prime(n) - 1) (prime(n) - 1)th powers.
%C A225578 It follows from Fermat's little theorem that a(n) is congruent to -1 mod the n-th prime.
%D A225578 R. K. Guy, Unsolved Problems in Number Theory, Springer, 1st edition, 1981. See section A17.
%D A225578 Paulo Ribemboim, The Little Book of Big Primes, New York, Springer-Verlag (1991): 17.
%H A225578 Seiichi Manyama, <a href="/A225578/b225578.txt">Table of n, a(n) for n = 1..76</a>
%F A225578 a(n) = Sum_{i=1..prime(n)-1} i^(prime(n) - 1).
%e A225578 a(2) = 5 because, since 3 is the second prime, we have 1^2 + 2^2 = 1 + 4 = 5.
%e A225578 a(3) = 354 because, since 5 is the third prime, we have 1^4 + 2^4 + 3^4 + 4^4 = 1 + 4 + 81 + 256 = 354.
%t A225578 Table[Sum[i^(Prime[n] - 1), {i, Prime[n] - 1}], {n, 15}]
%Y A225578 Cf. A055030, A031971, A204187.
%K A225578 easy,nonn
%O A225578 1,2
%A A225578 _Alonso del Arte_, May 10 2013