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A334975 Odd infinitary admirable numbers: the odd terms of A334974. 2
945, 43065, 46035, 80535, 354585, 403095, 430815, 437745, 442365, 2305875, 3525795, 4404105, 4891887, 5388495, 5927985, 6126645, 6220665, 6375105, 6537375, 7853625, 8109585, 8731125, 9071865, 9338595, 9784125, 13241745, 23760555, 33381855, 34592805, 35642295 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Of the first 10^4 infinitary admirable numbers only 9 are odd.

LINKS

Table of n, a(n) for n=1..30.

MATHEMATICA

fun[p_, e_] := Module[{b = IntegerDigits[e, 2], m}, m = Length[b]; Product[If[b[[j]] > 0, 1 + p^(2^(m - j)), 1], {j, 1, m}]]; isigma[1] = 1; isigma[n_] := Times @@ fun @@@ FactorInteger[n]; infDivQ[n_, 1] = True; infDivQ[n_, d_] := BitAnd[IntegerExponent[n, First /@ (f = FactorInteger[d])], (e = Last /@ f)] == e; infAdmQ[n_] := (ab = isigma[n] - 2 n) > 0 && EvenQ[ab] && ab/2 < n && Divisible[n, ab/2] && infDivQ[n, ab/2]; Select[Range[1, 5*10^5, 2], infAdmQ]

CROSSREFS

The infinitary version of A109729.

Intersection of A005408 and A334974.

Subsequence of A127666.

Cf. A329188, A334973.

Sequence in context: A335055 A133818 A334973 * A289953 A112491 A263889

Adjacent sequences:  A334972 A334973 A334974 * A334976 A334977 A334978

KEYWORD

nonn

AUTHOR

Amiram Eldar, May 18 2020

STATUS

approved

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Last modified June 18 17:32 EDT 2021. Contains 345120 sequences. (Running on oeis4.)