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A112640 Odd abundant numbers divisible neither by 5 nor 7. 6
28683369, 36165987, 38660193, 86050107, 108497961, 115980579, 131339637, 138428433, 140397543, 153393669, 160876287, 258150321, 277272567, 296394813, 315517059, 325493883, 347941737, 353761551, 372883797, 373715199, 392006043 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Subsequence of A064001 which itself is a subsequence of A005231. All 500 terms in b-file are divisible by 99. Cf. also A047802. - Zak Seidov, Mar 30 2011

LINKS

Zak Seidov, Table of n, a(n) for n = 1..500

C. Rivera, Puzzle 329. Odd abundant numbers not divided by 2 or 3.

MATHEMATICA

Do[If[Mod[n, 5]>0&&Mod[n, 7]>0&&DivisorSigma[1, n]>2n, Print[n]], {n, 28683369, 6*10^9, 2}] (* Zak Seidov, Mar 30 2011 *)

PROG

(PARI) is(n)=gcd(n, 70)==1 && sigma(n, -1)>2 \\ Charles R Greathouse IV, Feb 21 2017

CROSSREFS

Cf. A064001, A110585.

Sequence in context: A205933 A101639 A213914 * A200217 A306845 A104828

Adjacent sequences:  A112637 A112638 A112639 * A112641 A112642 A112643

KEYWORD

nonn

AUTHOR

Labos Elemer, Sep 15 2005

EXTENSIONS

Extended by Ray Chandler, Sep 19 2005

STATUS

approved

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Last modified August 21 23:04 EDT 2019. Contains 326169 sequences. (Running on oeis4.)