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A357763
Numbers m such that A357761(m) > A357761(k) for all k < m.
2
1, 2, 4, 8, 16, 28, 56, 112, 224, 448, 728, 1456, 2912, 5824, 10192, 11648, 20384, 27664, 40768, 55328, 110656, 221312, 442624, 885248, 1263808, 1770496, 2527616, 3430336, 5055232, 6860672, 10110464, 13721344, 16155776, 20220928, 24012352, 32311552, 48024704
OFFSET
1,2
COMMENTS
First differs from A330289 at n = 28.
Since A357761(2^n) = n + 1, A357761 is unbounded and this sequence is infinite.
The corresponding record values are 1, 2, 3, 4, 5, 6, 8, 10, 12, 14, 16, 20, 24, 28, 30, 32, ... .
LINKS
MATHEMATICA
f[n_] := -DivisorSum[n, (-1)^DigitCount[#, 2, 1] &]; fm = 0; s = {}; Do[f1 = f[n]; If[f1 > fm, fm = f1; AppendTo[s, n]], {n, 1, 10^5}]; s
PROG
(PARI) f(n) = -sumdiv(n, d, (-1)^hammingweight(d));
lista(nmax) = {my(fm = 0); for(n = 1, nmax, f1 = f(n); if(f1 > fm, fm = f1; print1(n, ", ")))};
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Amiram Eldar, Oct 12 2022
STATUS
approved