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A091231
How many more primes than irreducible GF(2)[X] polynomials there are in range [0,2^n].
2
0, 0, 0, 1, 1, 3, 4, 8, 13, 26, 45, 83, 152, 281, 523, 974, 1822, 3451, 6490, 12348, 23389, 44598, 85076, 162735, 311721, 598669, 1150613, 2215562, 4271844, 8247356, 15941844, 30849114, 59758104, 115878009, 224900328
OFFSET
0,6
FORMULA
a(0)=a(1)=0, a(n) = A007053(n)-A062692(n-1).
EXAMPLE
There are 11 primes (2,3,5,7,11,13,17,19,23,29,31) in range [0,32], while there are only 8 irreducible GF(2)[X]-polynomials in the same range: (2,3,7,11,13,19,25,31), thus a(5)=3.
CROSSREFS
Partial sums of A091232.
Sequence in context: A178749 A121980 A347493 * A250473 A049893 A307043
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jan 03 2004
STATUS
approved