A083158 Palindromes which are the arithmetic mean of two distinct palindromes.

2, 3, 4, 5, 6, 7, 8, 9, 22, 33, 44, 55, 66, 77, 88, 99, 101, 111, 121, 131, 141, 151, 161, 171, 181, 191, 202, 212, 222, 232, 242, 252, 262, 272, 282, 292, 303, 313, 323, 333, 343, 353, 363, 373, 383, 393, 404, 414, 424, 434, 444, 454, 464, 474, 484, 494, 505

Offset

1,1

Comments

The palindromes not in the sequence are 11, 10901, 109901,... (A114120). - Giovanni Resta, Feb 06 2006

Links

Table of n, a(n) for n=1..57.

Example

99 = (121+77)/2 is a member but 11 is not a member.
191 is in the sequence since it is the arithmetic mean of two distinct palindromes, 9 and 373.

Crossrefs

Cf. A083157, A114120.

Sequence in context: A318276 A274126 A108194 * A254956 A061013 A037264

Adjacent sequences: A083155 A083156 A083157 * A083159 A083160 A083161

Keyword

base,easy,nonn

Author

Amarnath Murthy and Meenakshi Srikanth (menakan_s(AT)yahoo.com), Apr 25 2003

Extensions

More terms from Giovanni Resta, Feb 06 2006

Status

approved