OFFSET
0,1
COMMENTS
a(n) has to be larger than the solution to Zeta(n)*(x-1)^n=x^n.
EXAMPLE
a(1)=5 since sigma(1)=1,sigma(2)=3,sigma(3)=4, sigma(4)=7, but sigma(5)=6.
PROG
(PARI) a(n) = {my(k = 2); while(sigma(k, n) > sigma(k-1, n), k++); k; } \\ Michel Marcus, Aug 18 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
John L. Drost, Oct 26 2004
STATUS
approved