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

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); };
A339898(n) = { my(x=A019565(2*n)); ((x-1)%A000265(eulerphi(x))); };

Crossrefs

Cf. A053575, A019565, A339809, A339821, A339971, A339899, A339901.

Cf. A339973 (positions of zeros).

Sequence in context: A127471 A309044 A240312 * A273163 A276695 A358096

Adjacent sequences: A339895 A339896 A339897 * A339899 A339900 A339901

Keyword

nonn

Author

Antti Karttunen, Dec 28 2020

Status

approved