A262682 Even bisection of A262680.

0, 0, 2, 0, 2, 0, 0, 0, 2, 0, 0, 0, 2, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 2, 0, 2, 0, 0, 2, 0, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 4, 2

Offset

0,3

Comments

Number of perfect squares (A000290) encountered before zero is reached when starting from k = 2n and repeatedly applying the map that replaces k by k - d(k), where d(k) is the number of divisors of k (A000005). This count includes n itself if it is a square, but excludes the zero.

Links

Antti Karttunen, Table of n, a(n) for n = 0..10082

Formula

a(n) = A262680(2*n).

Prog

(Scheme) (define (A262682 n) (A262680 (+ n n)))

Crossrefs

Cf. A000005, A000290, A010052, A049820, A155043, A262677, A262680, A262681.

Sequence in context: A160498 A089800 A079208 * A318983 A318982 A069851

Adjacent sequences: A262679 A262680 A262681 * A262683 A262684 A262685

Keyword

nonn

Author

Antti Karttunen, Oct 03 2015

Status

approved