OFFSET
1,2
COMMENTS
Also, the number of infinitary divisors of the numbers whose number of divisors is a power of 2.
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
FORMULA
MATHEMATICA
Select[DivisorSigma[0, Range[300]], # == 2^IntegerExponent[#, 2] &]
PROG
(PARI) lista(n) = select(x -> x >> valuation(x, 2) == 1, vector(n, i, numdiv(i)));
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Amiram Eldar, May 02 2024
STATUS
approved