A075767 Least m such that A(m) = -10^n, where A(n) = sigma(n) - 2n, the abundance of n.

1, 11, 101, 5090, 40028, 182525, 2000006, 44244716, 400000028, 4000000028, 2210000389844, 200000000006, 2157894737114, 160003470403376

Offset

0,2

Links

Table of n, a(n) for n=0..13.

Jason Earls, Some Smarandache-type sequences and problems concerning abundant and deficient numbers, in Smarandache Notions Journal (2004), Vol. 14.1, pp 265-270.

Mathematica

A[m_] := DivisorSigma[1, m]-2*m; Do[m = 1; While[A[m] != -10^n, m++ ]; Print[m], {n, 0, 9}] (* Ryan Propper, Oct 01 2006 *)

Crossrefs

Sequence in context: A233432 A052075 A070854 * A292014 A080176 A064490

Adjacent sequences: A075764 A075765 A075766 * A075768 A075769 A075770

Keyword

more,nonn

Author

Jason Earls, Oct 09 2002

Extensions

More terms from Ryan Propper, Oct 01 2006

a(10)-a(13) from Hiroaki Yamanouchi, Aug 24 2018

Status

approved