A362550 Number of even nontotients less than 10^n.

0, 13, 210, 2627, 29747, 319817, 3365629, 34962092, 360152096, 3688820638

Offset: 1

Author

Robert G. Wilson v, Apr 24 2023

Keywords

• nonn
• more

Examples

			a(1) = 0 since 2, 4, 6, and 8 are terms of A002202.
a(2) = 13 since there are 13 even nontotients less than 100, and they are 14,26,34,38,50,62,68,74,76,86,90,94 and 98.
		

Crossrefs

Cf. A002202, A005277, A072077.

Programs

PARI

a(n)=sum(k=1,10^n\2, !istotient(2*k)) \\ Charles R Greathouse IV, Apr 25 2023

Extensions

a(8)-a(10) from Charles R Greathouse IV, Apr 25 2023