OFFSET
1,1
REFERENCES
M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards Applied Math. Series 55, 1964 (and various reprintings), p. 840.
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards, Applied Math. Series 55, Tenth Printing, 1972 [alternative scanned copy].
EXAMPLE
d(1)=1 and d(2)=2; therefore neither are included. Members include 3 (2 divisors), 6 (4 divisors) and 60 (12 divisors); other nonmembers include 4 (3 divisors), 12 (6 divisors) and 5040 (60 divisors).
MAPLE
A036459:= proc(n) option remember;
procname(numtheory:-tau(n))+1;
end proc:
select(t -> A036459(t)::odd, [$1..1000]); # Robert Israel, Aug 31 2015
MATHEMATICA
a = {}; Do[Which[DivisorSigma[0, k] == k, 0, MemberQ[a, DivisorSigma[0, k]], 0, True, AppendTo[a, k]], {k, 109}]; a (* Michael De Vlieger, Aug 31 2015 *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Matthew Vandermast, Mar 16 2003
STATUS
approved