0,3

a(0)=0; thereafter if n occurs as a term of A219650, a(n)=its position in A219650, otherwise zero. This works as an "inverse" function for A219650 in a sense that a(A219650(n)) = n for all n.

Antti Karttunen, Table of n, a(n) for n = 0..10079

a(n) = A230412(n) * A230413(n).

a(n) = A230423(n)/2.

(Scheme)

(define (A230414 n) (* (A230412 n) (A230413 n)))

Cf. A219650, A230423, A230424. A219658 gives the positions of zeros after the first one. Analogous sequence for binary system: A213714.

Sequence in context: A188430 A013585 A261319 * A053653 A332629 A262174

Adjacent sequences: A230411 A230412 A230413 * A230415 A230416 A230417

nonn

Antti Karttunen, Oct 31 2013

approved