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A331857
a(n) is the greatest value obtained by partitioning the binary representation of n into consecutive blocks, and then reversing those blocks.
3
0, 1, 2, 3, 4, 6, 6, 7, 8, 12, 12, 14, 12, 14, 14, 15, 16, 24, 24, 28, 24, 26, 28, 30, 24, 28, 28, 30, 28, 30, 30, 31, 32, 48, 48, 56, 48, 52, 56, 60, 48, 52, 52, 58, 56, 58, 60, 62, 48, 56, 56, 60, 56, 58, 60, 62, 56, 60, 60, 62, 60, 62, 62, 63, 64, 96, 96
OFFSET
0,3
FORMULA
a(n)^A023416(n) = A073138(n) (where a^k denotes the k-th iterate of n).
a(n) >= n with equality iff n belongs to A023758.
EXAMPLE
For n = 6:
- the binary representation of 6 is "110",
- we can split it in 4 ways:
"110" -> "011" -> 3
"1" and "10" -> "1" and "01" -> 5
"11" and "0" -> "11" and "0" -> 6
"1" and "1" and "0" -> "1" and "1" and "0" -> 6
- we have 3 distinct values, the greatest being 6,
- hence a(6) = 6.
PROG
(PARI) See Links section.
CROSSREFS
See A331855 for the number of distinct values, and A331856 for the least value.
Sequence in context: A233569 A246593 A256999 * A073138 A342179 A362813
KEYWORD
nonn,base
AUTHOR
Rémy Sigrist, Jan 29 2020
STATUS
approved