A339551 - OEIS

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A339551

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

513059433, 3007912105, 4791685641, 11555664153, 44615854297, 111890605585, 121111724905, 163901238153

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OFFSET

1,1

COMMENTS

Analogous to A338453 as A339549 is analogous to A093653.

LINKS

Table of n, a(n) for n=1..8.

EXAMPLE

513059433 is a term since A339549(513059433) = A339549(513059434) = A339549(513059435) = 1166400.

MATHEMATICA

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

CROSSREFS

Cf. A000120, A093653, A338453, A339549.

Subsequence of A339550.

Sequence in context: A348798 A203261 A207041 * A319937 A186092 A034617

Adjacent sequences: A339548 A339549 A339550 * A339552 A339553 A339554

KEYWORD

nonn,base,more

AUTHOR

Amiram Eldar, Dec 08 2020

STATUS

approved