A222714 Smallest i such that prime(n) divides gcd(sigma(i), phi(i)) (cf. A009223).

3, 14, 88, 116, 989, 477, 6901, 7067, 6439, 10207, 4976, 10877, 13529, 44461, 79523, 22577, 250277, 62023, 107869, 161027, 75008, 49769, 55277, 183296, 75077, 612463, 381923, 412163, 712423, 153679, 32576, 137549, 450181, 154289, 1776377, 1642577, 491723, 637981, 3903791, 239777, 642251, 1572889, 1608983, 1192739, 2791489, 316409, 888731, 4773091, 4942243, 1256293

Offset: 1

Author

Phil Carmody, Mar 01 2013

Keywords

• nonn

Examples

			Given A009223 = 1, 1, 2, 1, 2, 2, 2, 1, 1, 2, 2, 4, 2, 6, 8, 1, 2, 3, ...
prime(1)=2 first divides A009223(3); prime(2)=3 first divides A009223(14)=6; prime(3)=5 first divides both sigma(88)=180 and phi(88)=40, so A222714(3)=88.
		

Crossrefs

Cf. A009223. Subsequence of A222713.

Programs

PARI

A009223_hunt(x)=local(n=0,g);while(n++,g=A009223(n);if(g%x,,return(n)));
for(x=1,50,print1(A009223_hunt(prime(x))", "))