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A338454
Starts of runs of 4 consecutive numbers with the same total binary weight of their divisors (A093653).
3
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
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
KEYWORD
nonn,base
AUTHOR
Amiram Eldar, Oct 28 2020
STATUS
approved