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 A358667 #10 Oct 20 2024 11:41:41 %S A358667 2,3,2,4,3,2,5,9,3,18,6,36,4,88,8,7,85,5,97,208,7,8,176,9,100,977,8,4, %T A358667 9,194,10,1521,1007,9,11,3,10,200,11,6034,4938,10,4433,12,2,11,375,13, %U A358667 6052,24709,13,30810,125,18,2,12,1517,16,96867,24733,51,216613,1014,1503,3 %N A358667 T(n,k) is the k-th integer j > 1 such that the sum of digits of n^j is a power of n (or -1 if no such k-th integer exists); table read by downward antidiagonals. %C A358667 T(11,1) is unknown at this time. %F A358667 T(n,1) = A358633(n). %F A358667 T(1,k) = k+1. %F A358667 T(2,k) = A095412(k+2). %F A358667 T(3,k) = A118872(k+2). %e A358667 Table begins: %e A358667 . %e A358667 n\k| 1 2 3 4 5 6 7 8 9 10 11 ... %e A358667 ---+------------------------------------------------------------------ %e A358667 1 | 2 3 4 5 6 7 8 9 10 11 12 ... %e A358667 2 | 2 3 9 36 85 176 194 200 375 1517 ... %e A358667 3 | 2 3 4 5 9 10 11 13 16 ... %e A358667 4 | 18 88 97 100 1521 6034 6052 96867 ... %e A358667 5 | 8 208 977 1007 4938 24709 24733 ... %e A358667 6 | 7 8 9 10 13 51 ... %e A358667 7 | 4 11 4433 30810 216613 ... %e A358667 8 | 3 12 125 1014 ... %e A358667 9 | 2 18 1503 ... %e A358667 10 | 2 3 ... %e A358667 11 | ? ... %e A358667 ... | ... %Y A358667 Cf. A095412, A118872, A358633. %K A358667 nonn,tabl %O A358667 1,1 %A A358667 _Jon E. Schoenfield_, Nov 25 2022