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 A375573 #7 Aug 20 2024 11:26:44 %S A375573 1,16,64,232,256,466,562,1024,1486,2048,4096,15226,16384,44552,65536, %T A375573 262144,1048576,4194304,16777216,67108864,268435456,1073741824, %U A375573 4294967296,17179869184,68719476736,274877906944,1099511627776,4398046511104,17592186044416,70368744177664 %N A375573 Numbers occurring at least three times in Bernoulli's triangle A008949. %C A375573 Equivalently, 1 together with numbers occurring at least three times in columns k >= 1 of Bernoulli's triangle. %C A375573 Equivalently, 1 together with numbers occurring at least twice in columns k >= 2 of Bernoulli's triangle. %C A375573 4^j is a term if j >= 0 and j != 1, because 4^j = A008949(2*j,2*j) = A008949(2*j+1,j) = A008949(4^j-1,1) for j >= 2 and A008949(i,0) = 1 for all i. Are 232, 466, 562, 1486, 2048, 15226, 44552 the only terms not of this form? There are no more such terms below 2^70. %C A375573 Are 1 and 4096 = A008949(12,12) = A008949(13,6) = A008949(90,2) = A008949(4095,1) the only numbers that occur at least 4 times? There are no more such numbers below 2^70. %Y A375573 Cf. A003015, A008949, A374796, A375570, A375572. %K A375573 nonn %O A375573 1,2 %A A375573 _Pontus von Brömssen_, Aug 19 2024