OFFSET
1,1
LINKS
Shyam Sunder Gupta, Table of n, a(n) for n = 1..5000
EXAMPLE
1242, 1248, 1254, 1260, 1266, 1272, 1278 is the smallest set of 7 consecutive abundant numbers in arithmetic progression so 1242 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 > 6, AppendTo[a, n - 6*cd]], m = 2; cd = n - z1]; z1 = n], {n, 19, 1000000}]; a
Select[Partition[Select[Range[80000], DivisorSigma[1, #]>2#&], 7, 1], Length[ Union[ Differences[#]]] ==1&][[All, 1]] (* Harvey P. Dale, Oct 15 2017 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Shyam Sunder Gupta, Nov 10 2013
STATUS
approved