A067284 a(n) = number of integers k such that k is not of the form m + reverse(m) for any m (cf. A067031) and A067030(n) occurs in the 'Reverse and Add' trajectory of k.

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 3, 5, 5, 8, 7, 12, 9, 1, 13, 21, 14, 1, 6, 11, 1, 4, 14, 1, 2, 9, 1, 2, 1, 2, 1, 22, 1, 2, 1, 2, 2, 3, 2, 3, 2, 3, 2, 16, 2, 3, 3, 5, 3, 4, 3, 5, 3, 4, 3, 30, 4, 6, 5, 5, 4, 6, 5, 5, 4, 6, 15, 8, 6, 6, 5, 8, 6, 6, 5, 8, 6, 9, 24, 7, 6, 9, 8, 7, 6, 9, 7, 12, 9, 8, 20

Offset

0,12

Comments

For an integer j not in A067030 there exists no integer k of the form m + reverse(m) such that j occurs in the trajectory of k. a(n) >= A067032(n); A067737 gives the terms of A067030 such that a(n) > A067032(n). A067288 gives the records in this sequence, A067287 gives the terms of A067030 at which these records are attained.

Links

Table of n, a(n) for n=0..96.

Index entries for sequences related to Reverse and Add!

Example

a(14) = 5, since A067030(14) = 55 and the five integers 7, 23, 32, 41, 50 are not of the form m + reverse(m) for any m and 55 occurs in the trajectory of each of them. a(25) = 11, since A067030(25) = 154 and the eleven integers 1, 25, 34, 43, 52, 59, 61, 68, 70, 86, 95 are not of the form m + reverse(m) for any m and 154 occurs in the trajectory of each of them.

Crossrefs

Cf. A067030, A067031, A067032, A067287, A067288, A067737.

Sequence in context: A174088 A304493 A208323 * A353272 A123339 A246104

Adjacent sequences: A067281 A067282 A067283 * A067285 A067286 A067287

Keyword

base,nonn

Author

Klaus Brockhaus, Feb 04 2002

Status

approved