A272652 a(n) is the smallest even number which has n inverse images under the map x -> x + (binary weight of x).

0, 14, 134, 4102, 87112285931760246646623899502532662132742, 1852673427797059126777135760139006525652319754650249024631321344126610074239106

Offset: 1

Author

Max Alekseyev and N. J. A. Sloane, May 13 2016

Keywords

• nonn

Comments

If the word "even" is omitted the sequence is A230303.

The next term is a(7) = 2^4233 + 130.

Examples

			The smallest number with two inverses is 14: the inverses are 11 = 1011_2 which maps to 11+3 = 14, and 12 = 1100_2 which maps to 12+2 = 14.
		

Crossrefs

Cf. A230303, A000120, A092391, A228085.