A319700 - OEIS

A319700

a(n) = A051953(A252463(n)).

0, 0, 1, 1, 1, 1, 1, 2, 2, 1, 1, 4, 1, 1, 4, 4, 1, 3, 1, 6, 6, 1, 1, 8, 3, 1, 4, 8, 1, 7, 1, 8, 8, 1, 7, 12, 1, 1, 12, 12, 1, 9, 1, 12, 8, 1, 1, 16, 5, 5, 14, 14, 1, 9, 9, 16, 18, 1, 1, 22, 1, 1, 12, 16, 13, 13, 1, 18, 20, 11, 1, 24, 1, 1, 12, 20, 11, 15, 1, 24, 8, 1, 1, 30, 15, 1, 24, 24, 1, 21, 15, 24, 30, 1, 19, 32, 1, 7, 16, 30, 1, 19, 1, 28, 22

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

OFFSET

1,8

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..16384

FORMULA

a(n) = A051953(A252463(n)).

PROG

(PARI)

A051953(n) = (n - eulerphi(n));

A064989(n) = {my(f); f = factor(n); if((n>1 && f[1, 1]==2), f[1, 2] = 0); for (i=1, #f~, f[i, 1] = precprime(f[i, 1]-1)); factorback(f)};

A252463(n) = if(!(n%2), n/2, A064989(n));