A262890 a(n) = total number of nodes in the finite subtrees branching from node n in the infinite trunk (A259934) of the tree generated by edge-relation A049820(child) = parent.

6, 0, 41, 0, 0, 5, 0, 16, 0, 2, 0, 1, 1, 26, 4, 0, 0, 3, 0, 1, 13, 0, 105, 2, 1, 1, 2, 5, 18, 7, 0, 0, 0, 1, 3, 3, 0, 0, 5, 0, 4, 13, 2, 7, 0, 0, 7, 6, 1, 0, 0, 0, 53, 0, 0, 0, 90, 1, 0, 5, 0, 2, 0, 1, 1, 0, 12, 1, 0, 3, 61, 0, 0, 0, 0, 0, 0, 2, 117, 7, 0, 2, 10, 0, 0, 1, 23, 1, 1, 1, 0, 0, 1, 0, 5, 1, 0, 3, 2, 2, 568, 1, 1, 1, 4, 1, 5, 9, 3, 0, 22, 1, 0, 9, 2, 1, 7, 0, 2, 10, 1, 1, 0

Offset

0,1

Links

Antti Karttunen, Table of n, a(n) for n = 0..8107

Formula

a(n) = Sum_{k = A082284(A259934(n)) .. A262686(A259934(n))} [A049820(k) = A259934(n)] * A262697(k).

(Here [ ] stands for Iverson bracket, giving as its result 1 only when A049820(k) = A259934(n), and 0 otherwise.)

Other identities. For all n >= 0:

a(n) = A262888(n) + A262889(n).

Prog

(Scheme)
(define (A262890 n) (let ((t (A259934 n))) (let loop ((s 0) (k (A262686 t))) (cond ((<= k t) s) ((= t (A049820 k)) (loop (+ s (A262697 k)) (- k 1))) (else (loop s (- k 1)))))))

Crossrefs

Cf. A000005, A049820, A082284, A259934, A262686, A262697, A262888, A262889.

Cf. A262892 (positions of zeros).

Cf. A262893 (partial sums).

Cf. also A255330.

Sequence in context: A051768 A262888 A262894 * A305331 A169769 A357966

Adjacent sequences: A262887 A262888 A262889 * A262891 A262892 A262893

Keyword

nonn

Author

Antti Karttunen, Oct 04 2015

Status

approved