A231093 - OEIS

A231093

Initial members of abundant octuplets, i.e., values of n such that (n, n+2, n+4, n+6, n+8, n+10, n+12, n+14) are all abundant numbers.

%I #10 Nov 05 2013 14:24:32

%S 221355126,402640540,668862580,739577140,1415514246,1598558646,

%T 1678915540,1714512246,1812156340,1829740086,1892686326,2097915966,

%U 2259080046,2452774780,2453605540,2521418740,2726361940,3118553740,3252749646,3318076446,4119153340,4748101660

%N Initial members of abundant octuplets, i.e., values of n such that (n, n+2, n+4, n+6, n+8, n+10, n+12, n+14) are all abundant numbers.

%H Donovan Johnson, <a href="/A231093/b231093.txt">Table of n, a(n) for n = 1..500</a>

%e 221355126, 221355128, 221355130, 221355132, 221355134, 221355136, 221355138, 221355140 are abundant, thus the smallest number is listed.

%t AbundantQ[n_] := DivisorSigma[1, n] > 2n; m = 0; a = {}; Do[If[AbundantQ[n], m = m + 1; If[m > 7, AppendTo[a, n - 14]], m = 0], {n, 2, 2000000000, 2}];a

%Y Cf. A005101, A108926, A231086, A231088, A231089, A231090, A231092.

%K nonn

%O 1,1

%A _Shyam Sunder Gupta_, Nov 03 2013