OFFSET

1,2

LINKS

Andrew Howroyd, Table of n, a(n) for n = 1..14

EXAMPLE

a(3)= 7, a(4) = 56 as there are 7 palindromes between 7 and 56: (8,9,11,22,33,44,55).

MATHEMATICA

Nest[Append[#, Block[{k = 0}, Catch@ Do[Which[k == #[[-1]], Throw[i]; Break[], PalindromeQ@ i, k++, True, Nothing], {i, #[[-1]] + 1, Infinity}]]] &, {1}, 5] (* Michael De Vlieger, Jan 28 2020 *)

PROG

(PARI) \\ Requires A002113.

a(n)={my(k=1, t=0); for(i=1, n, t=1+A002113(k); k += t + (t<10)); t} \\ Andrew Howroyd, Jan 27 2020

CROSSREFS

KEYWORD

base,nonn

AUTHOR

Amarnath Murthy, Nov 28 2004

EXTENSIONS

a(5)-a(7) from Ray Chandler, Dec 10 2004

a(8) from Donovan Johnson, Dec 03 2009

Terms a(9) and beyond from Andrew Howroyd, Jan 27 2020

STATUS

approved