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A236845
Numbers that occur in more than one way as results of "upward" remultiplication (GF(2)[X] -> N) of some number.
5
91, 117, 143, 171, 182, 234, 247, 273, 286, 333, 342, 351, 361, 364, 369, 429, 451, 468, 471, 494, 501, 513, 539, 546, 572, 609, 637, 666, 675, 684, 687, 702, 721, 722, 728, 738, 741, 803, 819, 847, 858, 902, 936, 942, 949, 957, 981, 988, 999, 1001, 1002, 1026, 1053, 1078, 1083, 1092, 1107, 1125
OFFSET
1,1
COMMENTS
Numbers that occur more than once in A234742.
Those terms that encode an irreducible polynomial in ring GF(2)[X] with their binary representation (that is, those that are in A014580) seem to occur also all in A091214 (that is, are a subsequence of the latter).
If n is a term, then 2n is also a term.
LINKS
PROG
(Scheme, with Antti Karttunen's IntSeq-library)
(define A236845 (MATCHING-POS 1 0 (lambda (n) (> (A236853 n) 1))))
CROSSREFS
Positions of terms larger than one in A236853.
Cf. also A236835.
Sequence in context: A261260 A161945 A140389 * A157345 A092125 A005935
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jan 31 2014
STATUS
approved