A352152 Reverse each run of consecutive nonzero digits in the decimal expansion 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 the nonnegative integers.

This sequence first differs from A321474 for n = 102: a(102) = 102 whereas A321474(102) = 201.

This sequence first differs from A333659 for n = 101: a(101) = 101 whereas A333659(101) = 110.

This sequence first differs from A336956 for n = 102: a(102) = 102 whereas A336956(102) = 201.

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).

Example

For n = 1024:
- we have two runs of consecutive nonzero digits: "1" and "24",
- the reverse of "1" is "1", that of "24" is "42",
- so a(1024) = 1042.

Prog

(Perl) sub a { my $v = shift; $v =~ s/[1-9]+/reverse($&)/ge; return $v; }
(Python)
from itertools import groupby
def A352152(n): return int(''.join(''.join(list(g) if k else list(g)[::-1]) for k, g in groupby(str(n), key=lambda x:x =='0'))) # Chai Wah Wu, Mar 08 2022

Crossrefs

Cf. A321474, A333659, A336956.

Sequence in context: A321474 A333659 A336956 * A225805 A068637 A004186

Adjacent sequences: A352149 A352150 A352151 * A352153 A352154 A352155

Keyword

nonn,base,easy

Author

Rémy Sigrist, Mar 06 2022

Status

approved