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A338453 Starts of runs of 3 consecutive numbers with the same total binary weight of their divisors (A093653). 5
3, 242, 243, 1837, 2361, 3693, 3728, 6061, 6457, 9782, 11181, 11721, 13855, 15177, 20017, 22591, 28021, 31461, 31887, 33098, 33993, 38137, 52016, 52112, 60321, 76897, 78542, 78745, 80461, 108394, 116017, 119541, 124453, 125493, 127117, 127417, 145369, 151805, 154113 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Numbers k such that A093653(k) = A093653(k+1) = A093653(k+2).
LINKS
EXAMPLE
3 is a term since A093653(3) = A093653(4) = A093653(5) = 3.
MATHEMATICA
f[n_] := DivisorSum[n, DigitCount[#, 2, 1] &]; s = {}; m = 3; fs = f /@ Range[m]; Do[If[Equal @@ fs, AppendTo[s, n - m]]; fs = Rest @ AppendTo[fs, f[n]], {n, m + 1, 155000}]; s
SequencePosition[Table[Total[DigitCount[Divisors[n], 2, 1]], {n, 160000}], {x_, x_, x_}][[All, 1]] (* Harvey P. Dale, Feb 04 2023 *)
CROSSREFS
Cf. A093653.
Subsequence of A338452.
Similar sequences: A005238, A006073, A045939.
Sequence in context: A069640 A324444 A236249 * A013778 A146313 A092799
KEYWORD
nonn,base
AUTHOR
Amiram Eldar, Oct 28 2020
STATUS
approved

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Last modified March 28 21:57 EDT 2024. Contains 371254 sequences. (Running on oeis4.)