A338454 Starts of runs of 4 consecutive numbers with the same total binary weight of their divisors (A093653).

242, 947767, 1041607, 2545015, 3275463, 8170983, 15720871, 21532430, 23752181, 25135885, 25595913, 27981703, 28226983, 30505142, 30962767, 33364805, 37264493, 49002661, 49766629, 52910454, 53408456, 57917191, 57952016, 58331576, 59230454, 60014053, 60723111, 63378005

Offset

1,1

Comments

Numbers k such that A093653(k) = A093653(k+1) = A093653(k+2) = A093653(k+3).

Links

Amiram Eldar, Table of n, a(n) for n = 1..10000

Example

242 is a term since A093653(242) = A093653(243) = A093653(244) = A093653(245) = 18.

Mathematica

f[n_] := DivisorSum[n, DigitCount[#, 2, 1] &]; s = {}; m = 4; fs = f /@ Range[m]; Do[If[Equal @@  fs, AppendTo[s, n - m]]; fs = Rest @ AppendTo[fs, f[n]], {n, m + 1, 10^7}]; s

Crossrefs

Cf. A093653.

Subsequence of A338452 and A338453.

Similar sequences: A006601, A045932, A045940.

Sequence in context: A022153 A335611 A194788 * A055554 A214105 A018871

Adjacent sequences: A338451 A338452 A338453 * A338455 A338456 A338457

Keyword

nonn,base

Author

Amiram Eldar, Oct 28 2020

Status

approved