A339898 - OEIS

A339898

a(n) = A019565(2n)-1 mod A000265(phi(A019565(2n))).

0, 0, 0, 0, 0, 2, 1, 2, 0, 2, 4, 4, 1, 5, 9, 14, 0, 2, 1, 2, 0, 2, 4, 5, 7, 8, 9, 14, 10, 32, 9, 29, 0, 0, 0, 0, 1, 2, 0, 2, 1, 0, 4, 4, 3, 11, 4, 14, 1, 2, 0, 2, 7, 5, 3, 2, 0, 2, 4, 14, 6, 20, 34, 14, 0, 2, 4, 5, 24, 20, 16, 23, 28, 41, 9, 29, 112, 68, 24, 74, 3, 11, 19, 5, 27, 2, 58, 14, 16, 50, 84, 119, 388, 356

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OFFSET

0,6

LINKS

Antti Karttunen, Table of n, a(n) for n = 0..8192

Antti Karttunen, Data supplement: n, a(n) computed for n = 0..65537

FORMULA

a(n) = A339809(2*n) modulo A339971(n), where A339971(n) = A053575(A019565(2n)).

PROG

(PARI)

A000265(n) = (n>>valuation(n, 2));

A019565(n) = { my(m=1, p=1); while(n>0, p = nextprime(1+p); if(n%2, m *= p); n >>= 1); (m); };