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A330340
a(n) is the least k such that A092213(n) = k + reverse(k) (where reverse(k) is the binary reverse of k, A030101(k)).
2
0, 1, 2, 4, 3, 6, 5, 7, 10, 16, 9, 14, 11, 20, 18, 15, 32, 17, 22, 26, 21, 19, 30, 34, 23, 27, 44, 31, 38, 64, 33, 50, 46, 37, 54, 35, 68, 45, 62, 39, 66, 76, 51, 84, 47, 55, 74, 70, 92, 63, 128, 65, 98, 78, 86, 73, 106, 69, 102, 94, 67, 132, 77, 110, 85, 118
OFFSET
0,3
LINKS
FORMULA
a(n) + A030101(a(n)) = A092213(n).
a(n) <= A331585(n).
EXAMPLE
For n = 3:
- A092213(3) = 5,
- 4 is the least k such that k + reverse(k) = 5,
- so a(3) = 4.
PROG
(PARI) See Links section.
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Rémy Sigrist, Jan 21 2020
STATUS
approved