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A347939 Primitive terms of A347936: terms of A347936 that are not multiples of other terms of A347936. 2
155925, 225225, 259875, 294525, 297675, 363825, 405405, 429975, 496125, 552825, 562275, 571725, 606375, 628425, 694575, 760725, 765765, 921375, 945945, 987525, 1044225, 1167075, 1195425, 1334025, 1412775, 1447875, 1486485, 1507275, 1526175, 1611225, 1640925, 1645875 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Since any positive odd multiple of a term of A347936 is also a term of A347936, the sequence A347936 consists of the positive odd multiple of this sequence.

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

EXAMPLE

The first 8 terms of this sequence are the same as those of A347936. But A347936(9) = 467775 = 3 * 155925 = 3 * A347936(1) is not a term of this sequence.

MATHEMATICA

abQ[n_] := DivisorSigma[1, n] > 2*n; s[n_] := DivisorSum[n, # &, abQ[#] &]; q[n_] := s[n] > 2*n && AllTrue[Most @ Divisors[n], ! q[#] &]; Select[Range[1, 300000, 2], q]

CROSSREFS

Subsequence A005101, A005231, A347936 and A347938.

Cf. A006038, A187795.

Sequence in context: A156118 A171658 A347936 * A177811 A341118 A129242

Adjacent sequences:  A347936 A347937 A347938 * A347940 A347941 A347942

KEYWORD

nonn

AUTHOR

Amiram Eldar, Sep 20 2021

STATUS

approved

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Last modified August 8 14:59 EDT 2022. Contains 356009 sequences. (Running on oeis4.)