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A329187 Initial members of admirable triples: numbers k such that (k, k+2, k+4) are all admirable numbers (A111592). 1
364, 17272, 54064, 383404, 1820812, 1945804, 2466604, 3283024, 3503164, 3820684, 3907984, 4407952, 5553712, 6095344, 6320524, 6820492, 7845232, 7966252, 8591212, 9841132, 10990864, 11841004, 12428272, 13695052, 13903372, 15032272, 15569932, 19007212, 19740304 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

EXAMPLE

364 is in the sequence since 364, 366, and 368 are all admirable numbers.

MATHEMATICA

admQ[n_] := (ab = DivisorSigma[1, n] - 2 n) > 0 && EvenQ[ab] && ab/2 < n && Divisible[n, ab/2]; k = 0; s = {}; Do[If[admQ[n], k++; If[k > 2, AppendTo[s, n - 4]], k = 0], {n, 6, 2*10^6, 2}]; s (* for even terms; after Shyam Sunder Gupta at A231088 *)

CROSSREFS

Subsequence of A109730, A111592, and A231088.

Sequence in context: A175114 A022045 A278002 * A107509 A140935 A249671

Adjacent sequences:  A329184 A329185 A329186 * A329188 A329189 A329190

KEYWORD

nonn

AUTHOR

Amiram Eldar, Nov 07 2019

STATUS

approved

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Last modified October 27 03:29 EDT 2021. Contains 348270 sequences. (Running on oeis4.)