cp's OEIS Frontend

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.

A339551 Starts of runs of 3 consecutive numbers with the same product of the binary weights of their divisors (A339549).

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%I A339551 #4 Dec 08 2020 17:05:54
%S A339551 513059433,3007912105,4791685641,11555664153,44615854297,111890605585,
%T A339551 121111724905,163901238153
%N A339551 Starts of runs of 3 consecutive numbers with the same product of the binary weights of their divisors (A339549).
%C A339551 Analogous to A338453 as A339549 is analogous to A093653.
%e A339551 513059433 is a term since A339549(513059433) = A339549(513059434) = A339549(513059435) = 1166400.
%t A339551 f[n_] := Times @@ (DigitCount[#, 2, 1] & /@ Divisors[n]); s = {}; m = 3; fs = f /@ Range[m]; Do[If[Equal @@  fs, AppendTo[s, n - m]]; fs = Rest @ AppendTo[fs, f[n]], {n, m + 1, 5*10^9}]; s
%Y A339551 Cf. A000120, A093653, A338453, A339549.
%Y A339551 Subsequence of A339550.
%K A339551 nonn,base,more
%O A339551 1,1
%A A339551 _Amiram Eldar_, Dec 08 2020