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A147613
Numbers that are not Jacobsthal numbers.
2
2, 4, 6, 7, 8, 9, 10, 12, 13, 14, 15, 16, 17, 18, 19, 20, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77
OFFSET
1,1
COMMENTS
The nonnegative integers not occurring in A001045.
A147612(a(n)) = 0.
The formula below is a consequence of the Lambek-Moser theorem.
FORMULA
a(n) = floor(-LambertW(-1, -(1/3)*log(2)*2^(3/2-n))/log(2) + 1/2). - Nicolas Normand (Nicolas.Normand(at)polytech.univ-nantes.fr), Nov 29 2017
MAPLE
a:=proc(n) floor(-LambertW(-1, -1/3*ln(2)*2^(3/2-n))/ln(2)+1/2) end:
seq(a(n), n=1..70); # Simon Plouffe, Nov 29 2017
MATHEMATICA
Complement[Range[m = 100], LinearRecurrence[{1, 2}, {0, 1}, m]] (* Jean-François Alcover, Feb 13 2018 *)
CROSSREFS
Sequence in context: A299491 A039098 A015860 * A155939 A114145 A153351
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Nov 08 2008
STATUS
approved