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A236835
Numbers that occur in more than one way as results of "downward" remultiplication (N -> GF(2)[X]) of some number.
9
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
1,1
COMMENTS
Numbers that occur more than once in A234741.
LINKS
FORMULA
For all n, A236379(a(n)) > 0.
EXAMPLE
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).
PROG
(Scheme, with Antti Karttunen's IntSeq-library)
(define A236835 (MATCHING-POS 1 0 (lambda (n) (> (A236833 n) 1))))
CROSSREFS
Positions of terms larger than one in A236833.
Cf. A236833, A236834. A091209 is NOT a subsequence.
Sequence in context: A313667 A313668 A236848 * A236844 A271468 A313669
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jan 31 2014
STATUS
approved