A321474 Reverse the nonzero digits of n.

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 21, 31, 41, 51, 61, 71, 81, 91, 20, 12, 22, 32, 42, 52, 62, 72, 82, 92, 30, 13, 23, 33, 43, 53, 63, 73, 83, 93, 40, 14, 24, 34, 44, 54, 64, 74, 84, 94, 50, 15, 25, 35, 45, 55, 65, 75, 85, 95, 60, 16, 26, 36, 46, 56, 66, 76

Offset

0,3

Comments

This sequence is a self-inverse permutation of nonnegative integers.

See A321464 for the ternary variant.

This sequence has similarities with A069799: here we reverse nonzero digits, there we reverse nonzero prime exponents.

Links

Rémy Sigrist, Table of n, a(n) for n = 0..10000

Index entries for sequences that are permutations of the natural numbers

Formula

a(10 * n) = 10 * a(n).

A136400(a(n)) = A136400(n).

Example

For n = 1024:
- 1024 has 3 nonzero digits: 1, 2 and 4,
- so we replace the first nonzero digit by the third, the third by the first (and the second remains in place),
- and we obtain a(1024) = 4021.

Prog

(PARI) a(n, base=10) = my (d=digits(n, base), t=Vecrev(select(sign, d)), i=0); for (j=1, #d, if (d[j], d[j] = t[i++])); fromdigits(d, base)

Crossrefs

Cf. A004086, A069799, A136400, A321464.

Sequence in context: A378808 A064222 A261294 * A333659 A336956 A352152

Adjacent sequences: A321471 A321472 A321473 * A321475 A321476 A321477

Keyword

nonn,base

Author

Rémy Sigrist, Nov 11 2018

Status

approved