OFFSET
1,1
LINKS
Giovanni Resta, Table of n, a(n) for n = 1..88 (terms < 10^13)
MATHEMATICA
nn = 10^7; t = {}; sig0 = 1; sig1 = 3; Do[sig2 = DivisorSigma[1, n + 2]; If[sig0 == sig1 + sig2, AppendTo[t, n]]; sig0 = sig1; sig1 = sig2, {n, nn}]; t (* T. D. Noe, Jun 05 2013 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Alex Ratushnyak, Jun 05 2013
EXTENSIONS
a(17)-a(23) from Donovan Johnson, Jun 05 2013
STATUS
approved