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A156943 Odd numbers not congruent to 25 whose abundancy is odd. 2
81162081, 138791961, 173369889, 441882441, 730458729, 1091179089, 1249127649, 1524043521, 1560329001, 1744649361, 2286465489, 2606204601, 3255501249, 3976941969, 4770526761, 5567099769, 6574128561, 6800806089, 7584145569 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Number of terms <10^n: 0, 0, 0, 0, 0, 0, 0, 1, 5, 25, 63, ..., .

LINKS

R. G. Wilson v, Table of n, a(n) for n=1,...,1005

MATHEMATICA

f[n_] := DivisorSigma[1, n] - 2 n; Select[ Range[1, 7775536039, 2], Mod[f@#, 2]!=5 f@# > 0 &]

CROSSREFS

Cf. A156903, A156942.

Sequence in context: A210164 A119075 A136965 * A120316 A118079 A186091

Adjacent sequences:  A156940 A156941 A156942 * A156944 A156945 A156946

KEYWORD

nonn

AUTHOR

Robert G. Wilson v, Feb 18 2009

STATUS

approved

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Last modified January 24 21:49 EST 2022. Contains 350565 sequences. (Running on oeis4.)