OFFSET

1,1

COMMENTS

The unitary version of A057978. a(5)-a(8) were taken from the paper by Pomerance and Yang.

LINKS

Carl Pomerance and Hee-Sung Yang, Variant of a theorem of ErdÅ‘s on the sum-of-proper-divisors function, Mathematics of Computation, Vol. 83, No. 288 (2014), pp. 1903-1913.

CROSSREFS

KEYWORD

nonn,more

AUTHOR

Amiram Eldar, Jul 24 2017

STATUS

approved