A130670 Smallest k such that phi(x) = k has exactly n even solutions.

1, 2, 4, 8, 16, 32, 24, 80, 48, 160, 72, 216, 96, 792, 360, 144, 192, 1056, 1512, 1080, 240, 288, 432, 1248, 3200, 1200, 768, 3120, 480, 576, 2496, 720, 1536, 864, 6000, 3600, 2016, 3072, 960, 3168, 3744, 1152, 11664, 2688, 2400, 2160, 9792, 1728, 6240, 9072

Offset: 1

Author

Franz Vrabec, Jun 27 2007

Keywords

• nonn

Examples

			a(3) = 4 because there are 3 even solutions (8, 10, 12) of phi(x) = 4 and for all k < 4 the number of even solutions of phi(x) = k is unequal to 3.
		

Links

• Vladeta Jovovic and Donovan Johnson, Table of n, a(n) for n = 1..1000 (first 100 terms from Vladeta Jovovic)

Crossrefs

Cf. A007374, A130669.