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A228963 Smallest sets of 6 consecutive abundant numbers in arithmetic progression. The initial abundant number is listed. 4
228, 1002, 1242, 1248, 2328, 3348, 4182, 4362, 4428, 5202, 5268, 6702, 6708, 6882, 7962, 7968, 8142, 8382, 8982, 9822, 9888, 10242, 11568, 11922, 11988, 12162, 12168, 12588, 13248, 13422, 13842, 13848, 14022, 14088, 14508, 15282, 15522, 15528, 16362, 16368 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Shyam Sunder Gupta, Table of n, a(n) for n = 1..5000

EXAMPLE

228, 234, 240, 246, 252, 258 is the smallest set of 6 consecutive abundant numbers in arithmetic progression so 228 is in the list.

MATHEMATICA

AbundantQ[n_] := DivisorSigma[1, n] > 2 n; m = 2; z1 = 18; cd = 6; a = {}; Do[If[AbundantQ[n], If[n - z1 == cd, m = m + 1; If[m > 5, AppendTo[a, n - 5*cd]], m = 2; cd = n - z1]; z1 = n], {n, 19, 1000000}]; a

CROSSREFS

Cf. A005101, A228433, A228844, A228961, A228962.

Sequence in context: A172531 A258557 A206005 * A252220 A263301 A053174

Adjacent sequences:  A228960 A228961 A228962 * A228964 A228965 A228966

KEYWORD

nonn

AUTHOR

Shyam Sunder Gupta, Nov 10 2013

STATUS

approved

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Last modified October 28 13:26 EDT 2021. Contains 348329 sequences. (Running on oeis4.)