

A222714


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


2



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
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,1


LINKS

Table of n, a(n) for n=1..50.


EXAMPLE

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.


PROG

(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))", "))


CROSSREFS

Cf. A009223. Subsequence of A222713.
Sequence in context: A132624 A121587 A185323 * A199548 A038170 A007840
Adjacent sequences: A222711 A222712 A222713 * A222715 A222716 A222717


KEYWORD

nonn


AUTHOR

Phil Carmody, Mar 01 2013


STATUS

approved



