A068064 a(n) = number of integers k such that palindrome A068062(n) = k + reverse(k).

1, 1, 1, 1, 1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 1, 9, 1, 1, 1, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8, 9, 9, 9, 9, 9, 1, 10, 3, 4, 5, 6, 7, 8, 9, 10, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 4, 8, 12, 16, 20, 24

Offset

1,7

Comments

The number of representations of a palindrome as a + b, where b = reverse(a); if a = reverse(b) and a is different from b, then a + b and b + a count as different representations.

Links

Table of n, a(n) for n=1..95.

Example

a(9) = 4, since A068062(9) = 44 and for k = 13, 22, 31, 40 we have 44 = k + reverse(k).
a(16) = 9, since A068062(16) = 121 and for k = 29, 38, 47, 56, 65, 74, 83, 92, 110 we have 121 = k + reverse(k).

Crossrefs

Cf. A002113, A067030, A067032, A068062.

Sequence in context: A112875 A113018 A113009 * A152147 A333830 A067032

Adjacent sequences: A068061 A068062 A068063 * A068065 A068066 A068067

Keyword

base,nonn

Author

Klaus Brockhaus, Feb 16 2002

Extensions

Offset corrected by Sean A. Irvine, Jan 23 2024

Status

approved