A325566 a(n) is the largest divisor d of n such that A048720(A065621(d),n/d) = n.

1, 2, 1, 4, 1, 2, 1, 8, 3, 2, 1, 4, 1, 2, 1, 16, 1, 6, 1, 4, 3, 2, 1, 8, 1, 2, 1, 4, 1, 2, 1, 32, 11, 2, 5, 12, 1, 2, 1, 8, 1, 6, 1, 4, 3, 2, 1, 16, 7, 2, 1, 4, 1, 2, 1, 8, 1, 2, 1, 4, 1, 2, 1, 64, 13, 22, 1, 4, 1, 10, 1, 24, 1, 2, 5, 4, 1, 2, 1, 16, 1, 2, 1, 12, 1, 2, 1, 8, 1, 6, 1, 4, 3, 2, 1, 32, 1, 14, 1, 4, 1, 2, 1, 8, 7

Offset

1,2

Links

Antti Karttunen, Table of n, a(n) for n = 1..16383

Antti Karttunen, Data supplement: n, a(n) computed for n = 1..65537

Prog

(PARI)
A048720(b, c) = fromdigits(Vec(Pol(binary(b))*Pol(binary(c)))%2, 2);
A065621(n) = bitxor(n-1, n+n-1);
A325566(n) = fordiv(n, d, if(A048720(A065621(n/d), d)==n, return(n/d)));

Crossrefs

Cf. A048720, A065621, A325565, A325567, A325570 (positions of ones).

Sequence in context: A076775 A357689 A324873 * A218621 A079891 A108738

Adjacent sequences: A325563 A325564 A325565 * A325567 A325568 A325569

Keyword

nonn

Author

Antti Karttunen, May 09 2019

Status

approved