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A091232
How many more primes than irreducible GF(2)[X] polynomials there are in range [2^n,2^(n+1)].
1
0, 0, 1, 0, 2, 1, 4, 5, 13, 19, 38, 69, 129, 242, 451, 848, 1629, 3039, 5858, 11041, 21209, 40478, 77659, 148986, 286948, 551944, 1064949, 2056282, 3975512, 7694488, 14907270, 28908990, 56119905, 109022319, 211980753
OFFSET
0,5
FORMULA
a(0)=a(1)=0, a(n) = A036378(n+1)-A001037(n).
EXAMPLE
There are 5 primes (17,19,23,29,31) in range [16,32], while there are only 3 irreducible GF(2)[X]-polynomials in the same range: (19,25,31), thus a(4)=2.
CROSSREFS
First differences of A091231.
Sequence in context: A191830 A155944 A350087 * A336398 A209337 A243004
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jan 03 2004
STATUS
approved