A230414 Inverse function for injection A219650.

0, 1, 2, 0, 0, 3, 4, 5, 0, 0, 6, 7, 8, 0, 0, 9, 10, 11, 0, 0, 0, 0, 0, 12, 13, 14, 0, 0, 15, 16, 17, 0, 0, 18, 19, 20, 0, 0, 21, 22, 23, 0, 0, 0, 0, 0, 24, 25, 26, 0, 0, 27, 28, 29, 0, 0, 30, 31, 32, 0, 0, 33, 34, 35, 0, 0, 0, 0, 0, 36, 37, 38, 0, 0, 39, 40, 41

Offset

0,3

Comments

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.

Links

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

Formula

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

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

Prog

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

Crossrefs

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

Keyword

nonn

Author

Antti Karttunen, Oct 31 2013

Status

approved