A262681 - OEIS

A262681

Odd bisection of A262680.

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 3, 3, 1

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

OFFSET

0,85

COMMENTS

Number of perfect squares (A000290) encountered before zero is reached when starting from k = 2n+1 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)+1).

PROG

(Scheme) (define (A262681 n) (A262680 (+ n n 1)))

CROSSREFS

Cf. A000005, A000290, A010052, A049820, A155043, A262677, A262680, A262682.

Sequence in context: A103496 A345441 A267863 * A076498 A110268 A058965

Adjacent sequences: A262678 A262679 A262680 * A262682 A262683 A262684

KEYWORD

nonn

AUTHOR

Antti Karttunen, Oct 03 2015

STATUS

approved