A178889 Numbers n such that R(n) (n-reversed) appears to the left of n in the string 12345678910111213....

19, 21, 29, 31, 32, 39, 41, 42, 43, 49, 51, 52, 53, 54, 59, 61, 62, 63, 64, 65, 69, 71, 72, 73, 74, 75, 76, 79, 81, 82, 83, 84, 85, 86, 87, 89, 91, 92, 93, 94, 95, 96, 97, 98, 99, 101, 110, 111, 119, 120, 121, 130, 131, 140, 141, 150, 151, 160, 161, 170, 171, 180, 181

Offset

1,1

Comments

Consider the infinite string of digits A007908(row->infinity). Whenever the digit-reversed variant of n, R(n) = A004086(n), appears ahead of n in that string, adjoin n to the current sequence.

Links

Table of n, a(n) for n=1..63.

Example

19 is generated where 9 meets 10, 12345678(91)01112131415161718(19)20...
21 is generated by 1 and 2: (12)34567891011121314151617181920(21)22...
29 is generated where 19 joins 20: 1234567891011121314151617181(92)02122232425262728(29)30...

Crossrefs

Cf. A116700.

Sequence in context: A347343 A054864 A158232 * A167998 A050714 A113868

Adjacent sequences: A178886 A178887 A178888 * A178890 A178891 A178892

Keyword

nonn,base,easy

Author

Paolo P. Lava & Giorgio Balzarotti, Jun 21 2010

Extensions

Definition shortened, examples detailed, keyword:base added by R. J. Mathar, Jul 13 2010

Status

approved