A236835 Numbers that occur in more than one way as results of "downward" remultiplication (N -> GF(2)[X]) of some number.

5, 10, 15, 17, 20, 23, 27, 29, 30, 34, 39, 40, 45, 46, 51, 53, 54, 57, 58, 60, 65, 68, 71, 75, 78, 80, 83, 85, 90, 92, 95, 99, 101, 102, 105, 106, 107, 108, 113, 114, 116, 119, 120, 127, 129, 130, 135, 136, 139, 141, 142, 147, 150, 151, 153, 156, 160, 163, 165

Offset: 1

Author

Antti Karttunen, Jan 31 2014

Keywords

• nonn

Comments

Numbers that occur more than once in A234741.

Examples

			5 occurs here, because it occurs in A234741 both as A234741(5)=5 and A234741(9)=5, as A048720(3,3)=5.
43 do not occur here, as although it is a term of A091209, it only occurs at A234741(43) as it cannot be obtained by other means as a carryless product than as 43 = A048720(3,25).
		

Links

• Antti Karttunen, Table of n, a(n) for n = 1..3385

Crossrefs

Positions of terms larger than one in A236833.

Cf. A236833, A236834. A091209 is NOT a subsequence.

Formula

For all n, A236379(a(n)) > 0.