A176315 Partials sums of A007080.

1, 3, 13, 165, 7901, 1383853, 879285501, 2047199658621, 17660268902020093, 569790880105867285245, 69280640454268889757533693

Offset: 1

Author

Jonathan Vos Post, Apr 15 2010

Keywords

• nonn

Comments

Partials sums of number of labeled Eulerian digraphs with n nodes. The subsequence of primes in this partial sum begins: 3, 13, 7901, 1383853, 17660268902020093.

Examples

			a(5) = 1 + 2 + 10 + 152 + 7736 = 7901 is prime.
		

Crossrefs

Cf. A007080.

Formula

a(n) = SUM[i=1..n] A007080(i).