A302854 Inverse of A302853: if A302853(k) = n, a(n) = k, or -1 if n does not occur in A302853.

0, 1, 3, 2, 5, 25, 4, 26, 7, 8, 10, 9, 6, 28, 11, 27, 13, 14, 16, 15, 18, 30, 17, 31, 20, 21, 23, 22, 19, 29, 12, 24, 65, 66, 7483, 7484, 70, 90, 7488, 7508, 68, 67, 7486, 7485, 69, 91, 7487, 7509, 72, 73, 7490, 7491, 71, 93, 7489, 7511, 75, 74, 7493, 7492, 76, 92, 7494, 7510, 33, 34, 36, 35, 38, 58, 37, 59, 40, 41, 43, 42, 39

Offset

0,3

Comments

This is a left inverse of A302853, and also the right inverse if A282291 (and thus also A302853) is surjective (a permutation of natural numbers), in which case the fallback-clause is unnecessary.

Links

Antti Karttunen, Table of n, a(n) for n = 0..259

Formula

For all n >= 0, a(A302853(n)) = n.

Prog

(PARI)
\\ For other needed code, follow A050376 and A282291:
A052330(n) = { my(p=1, i=1); while(n>0, if(n%2, p *= A050376(i)); i++; n >>= 1); (p); };
A302854(n) = (A304090(A052330(n))-1);

Crossrefs

Cf. A302853 (inverse).

Sequence in context: A103938 A304534 A085973 * A248243 A005265 A005266

Adjacent sequences: A302851 A302852 A302853 * A302855 A302856 A302857

Keyword

nonn

Author

Antti Karttunen, May 17 2018

Status

approved