A234017 Inverse function for injection A055938.

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

Offset

0,6

Comments

a(0)=0; thereafter if n occurs as a term of A055938, a(n)=its position in A055938, otherwise zero. This works as an "inverse" function for A055938 in a sense that a(A055938(n)) = n for all n.

a(n)*A213714(n) = 0 for all n.

Links

Antti Karttunen, Table of n, a(n) for n = 0..8191

Indranil Ghosh, Python program to generate the sequence

Formula

a(n) = (1-A079559(n)) * A234016(n).

Prog

(Scheme) (define (A234017 n) (* (- 1 (A079559 n)) (A234016 n)))

Crossrefs

Cf. also A079559, A234016, A055938, A213714, A233275, A233277.

Sequence in context: A292596 A011023 A284610 * A182057 A260928 A097027

Adjacent sequences: A234014 A234015 A234016 * A234018 A234019 A234020

Keyword

nonn

Author

Antti Karttunen, Dec 18 2013

Status

approved