OFFSET
1,6
COMMENTS
LINKS
Antti Karttunen, Table of n, a(n) for n = 1..10000
FORMULA
a(1) = 1; a(n) = 1 if n is prime, otherwise a(n) = A070824(n).
a(1) = 1; a(n) = 1 if n is prime, otherwise a(n) = A032741(n) - 1.
a(n) = max(1, A000005(n)-2). - Robert Israel, Jan 20 2016
MAPLE
seq(max(1, numtheory:-tau(n)-2), n=1..100); # Robert Israel, Jan 20 2016
MATHEMATICA
Array[DivisorSigma[0, #] - 2 &, {80}] /. n_ /; n < 2 -> 1 (* Michael De Vlieger, Jan 16 2016 *)
PROG
(PARI) A264440(n) = max(1, numdiv(n)-2); \\ After Robert Israel's formula. - Antti Karttunen, May 25 2017
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Wolfdieter Lang, Jan 16 2016
STATUS
approved