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A376686
a(n) is the unique k such that A376677(k) is the reversal of A376677(n), or -1 if no such k exists.
2
1, 2, 3, 5, 4, 6, 10, 8, 12, 7, 11, 9, 15, 21, 13, 19, 17, 18, 16, 22, 14, 20, 23, 32, 28, 30, 35, 25, 33, 26, 34, 24, 29, 31, 27, 36, 46, 53, 50, 40, 52, 44, 48, 42, 54, 37, 49, 43, 47, 39, 51, 41, 38, 45, 60, 76, 66, 63, 79, 55, 71, 65, 58, 74, 62, 57, 67
OFFSET
1,2
COMMENTS
Is this sequence a permutation of the positive integers?
EXAMPLE
The first terms, alongside the corresponding terms of A376677, are:
n a(n) A376677(n) A376677(a(n))
-- ---- ---------- -------------
1 1 1 1
2 2 2 2
3 3 11 11
4 5 12 21
5 4 21 12
6 6 22 22
7 10 112 211
8 8 121 121
9 12 122 221
10 7 211 112
11 11 212 212
12 9 221 122
13 15 1121 1211
14 21 1122 2211
15 13 1211 1121
16 19 1212 2121
PROG
(PARI) \\ See Links section.
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Rémy Sigrist, Oct 01 2024
STATUS
approved