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 A229310 #10 Oct 21 2013 09:47:46 %S A229310 7,10,26,55,57,136,155,222,253,737,876,1027,1081,1552,1711,1751,1962, %T A229310 3197,3403,3775,3916,4401,5671,6176,6567,8251,8515,8702,9316,11026, %U A229310 12195,12742,13301,13861,14878,15657,15931,18145,20242,22387,23126,25651,26202 %N A229310 Primitive numbers in A229306. %H A229310 Jose María Grau, A. M. Oller-Marcen, and J. Sondow, <a href="http://arxiv.org/abs/1309.7941">On the congruence 1^n + 2^n +... + n^n = d (mod n), where d divides n</a> %t A229310 g[n_] := Mod[Sum[PowerMod[i, n, n], {i, 1, n}], n]; tachar[lis_, num_] := Select[lis, ! IntegerQ[#1/num] &];primi[{}]={}; primi[lis_] := Join[{lis[[1]]}, primi[tachar[lis, lis[[1]]]]]; primi@Select[Range[500], !g[6*#] == # &] %Y A229310 Cf. A014117 (numbers n such that A031971(n)==1 (mod n)). %Y A229310 Cf. A229300 (numbers n such that A031971(1806*n)== n (mod n*1806)). %Y A229310 Cf. A229301 (numbers n such that A031971(42*n) == n (mod 42*n)). %Y A229310 Cf. A229302 (numbers n such that A031971(6*n) == n (mod 6*n)). %Y A229310 Cf. A229303 (numbers n such that A031971(2*n) == n (mod 2*n)). %Y A229310 Cf. A229304 (numbers n such that A031971(1806*n) <> n (mod n*1806)). %Y A229310 Cf. A229305 (numbers n such that A031971(42*n) <> n (mod 42*n)). %Y A229310 Cf. A229306 (numbers n such that A031971(6*n) <> n (mod 6*n)). %Y A229310 Cf. A229307 (numbers n such that A031971(2*n) <> n (mod 2*n)). %Y A229310 Cf. A229308 (primitive numbers in A229304). %Y A229310 Cf. A229309 (primitive numbers in A229305). %Y A229310 Cf. A229310 (primitive numbers in A229306). %Y A229310 Cf. A229311 (primitive numbers in A229307). %K A229310 nonn %O A229310 1,1 %A A229310 _José María Grau Ribas_, Sep 24 2013