A337223 a(n) is the least number that can be obtained by replacing some cube XXX in the binary expansion of n by X.

0, 1, 2, 3, 4, 5, 6, 1, 2, 9, 10, 11, 12, 13, 2, 3, 4, 5, 18, 19, 20, 21, 22, 5, 6, 25, 26, 27, 4, 5, 6, 7, 8, 9, 10, 11, 36, 37, 38, 9, 10, 41, 2, 43, 44, 45, 10, 11, 12, 13, 50, 51, 52, 53, 54, 13, 8, 9, 10, 11, 12, 13, 14, 3, 4, 17, 18, 19, 20, 21, 22, 17

Offset: 0

Author

Rémy Sigrist, Aug 19 2020

Keywords

• nonn
• base

Comments

Leading zeros in binary expansions are ignored.

Fixed points correspond to A286262.

Examples

			The first terms, in decimal and in binary, are:
  n   a(n)  bin(n)  bin(a(n))
  --  ----  ------  ---------
   0     0       0          0
   1     1       1          1
   2     2      10         10
   3     3      11         11
   4     4     100        100
   5     5     101        101
   6     6     110        110
   7     1     111          1
   8     2    1000         10
   9     9    1001       1001
  10    10    1010       1010
  11    11    1011       1011
  12    12    1100       1100
  13    13    1101       1101
  14     2    1110         10
  15     3    1111         11
  16     4   10000        100
		

Links

• Rémy Sigrist, Table of n, a(n) for n = 0..8192
• Rémy Sigrist, PARI program for A337223
• Index entries for sequences related to binary expansion of n

Crossrefs

Cf. A286262, A297405, A337222, A337224.

Programs

PARI

See Links section.

Formula

a(A297405(n)) = n for any n > 0.