

A318534


Lexicographically first sequence of distinct positive integers such that [a(n) + a(n+1)] or [a(n)  a(n+1)] is a palindrome in base 10.


1



1, 2, 3, 4, 5, 6, 16, 7, 15, 18, 9, 13, 20, 12, 10, 23, 21, 34, 26, 29, 37, 40, 32, 24, 31, 35, 27, 17, 38, 28, 49, 39, 60, 41, 8, 14, 19, 25, 30, 36, 52, 47, 54, 43, 45, 56, 55, 11, 22, 44, 33, 66, 65, 46, 42, 57, 64, 67, 74, 77, 84, 87, 94, 97, 105, 76, 75, 86, 85, 96, 95, 107, 115, 117, 125, 127, 135, 137, 145, 147, 48
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OFFSET

1,2


COMMENTS

Is this sequence a permutation of the positive integers?


LINKS

JeanMarc Falcoz, Table of n, a(n) for n = 1..10001


EXAMPLE

The sequence starts with 1,2,3,4,5,6,16,7,15,18,9,... and we see that [1 + 2] is a palindrome (3); [2 + 3] is a palindrome (5); [3 + 4] is a palindrome (7); [4 + 5] is a palindrome (9); [5 + 6] is a palindrome (11); [6 + 16] is a palindrome (22); [16  7] is a palindrome (9); [7 + 15] is a palindrome (22); etc.


CROSSREFS

Cf A228730 (Lexicographically earliest sequence of distinct nonnegative integers such that the sum of two consecutive terms is a palindrome in base 10).
Sequence in context: A065637 A039061 A138987 * A265405 A171610 A004835
Adjacent sequences: A318531 A318532 A318533 * A318535 A318536 A318537


KEYWORD

base,look,nonn


AUTHOR

JeanMarc Falcoz and Eric Angelini, Aug 28 2018


STATUS

approved



