OFFSET
1,1
COMMENTS
2.321567864518414051603264113617... = [0, 0, 2, 3, 9, 9, 20, 21, 32, 37, 54, 50, 77, 81, 96, ...]
LINKS
Paolo P. Lava, Table of n, a(n) for n = 1..1000
MAPLE
MATHEMATICA
digits=100; RealDigits[FromContinuedFraction[Table[n(n + 1)/2 - DivisorSigma[1, n], {n, digits}]], 10, digits][[1]] (* Stefano Spezia, Aug 02 2024 *)
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Paolo P. Lava, Jun 05 2013
STATUS
approved