A193254 Sum of odd divisors of lambda(n).

1, 1, 1, 1, 1, 1, 4, 1, 4, 1, 6, 1, 4, 4, 1, 1, 1, 4, 13, 1, 4, 6, 12, 1, 6, 4, 13, 4, 8, 1, 24, 1, 6, 1, 4, 4, 13, 13, 4, 1, 6, 4, 32, 6, 4, 12, 24, 1, 32, 6, 1, 4, 14, 13, 6, 4, 13, 8, 30, 1, 24, 24, 4, 1, 4, 6, 48, 1, 12, 4, 48, 4, 13, 13, 6, 13, 24, 4, 56, 1, 40, 6, 42, 4, 1, 32, 8, 6, 12, 4, 4, 12, 24, 24, 13, 1, 4, 32, 24, 6, 31, 1, 72, 4, 4

Offset: 1

Author

Michel Lagneau, Jul 22 2011

Keywords

• nonn

Comments

Lambda is the function in A002322.

Examples

			a(19) = 13 because lambda(19) = 18 and the sum of the 3 odd divisors {1, 3, 9} is 13.
		

Links

• Antti Karttunen, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A002322, A000593, A193169, A193454.

Programs

Mathematica

Table[Total[Select[Divisors[CarmichaelLambda[n]], OddQ[ # ]&]], {n, 67}]

PARI

a(n) = sumdiv(lcm(znstar(n)[2]), d, d*(d%2));

Formula

a(n) = A000593(A002322(n)).

Extensions

More terms from Antti Karttunen, Aug 22 2017