A222811 Number of n-digit numbers N such that the reversal of N divides N.

9, 18, 111, 212, 1128, 2067, 11123, 20270, 110440, 200971, 1101475, 2003592, 11005388

Offset

1,1

Comments

Suggested by A214927.

Even terms are roughly double the previous term. - David Consiglio, Jr., Mar 22 2013

Links

Table of n, a(n) for n=1..13.

David Consiglio, Jr., C++ program

N. J. A. Sloane, 2178 And All That, Fib. Quart., 52 (2014), 99-120.

Example

Some of the smallest solutions are:
[1, 2, 3, 4, 5, 6, 7, 8, 9] (so a(1) = 9),
[10, 11, 20, 22, 30, 33, 40, 44, 50, 55, 60, 66, 70, 77, 80, 88, 90, 99] (so a(2) = 18),
[100, 101, 110, 111, 121, 131, 141, 151, 161, 171, 181, 191, 200, 202, 212, 220, 222, 232, 242, 252, 262, 272, 282, 292, 300, 303, 313, 323, 330, 333, 343, 353, ...]

Crossrefs

Cf. A214927, A222809, A222810, A222812.

Sequence in context: A033651 A050250 A080453 * A002169 A050685 A278588

Adjacent sequences: A222808 A222809 A222810 * A222812 A222813 A222814

Keyword

nonn,base,more

Author

N. J. A. Sloane, Mar 10 2013

Extensions

a(8) - a(11) from David Consiglio, Jr., Mar 22 2013

a(12)-a(13) from Giovanni Resta, Apr 01 2013

Status

approved