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A091227
Inverse function of A014580: position in A014580 if the n-th GF(2)[X] polynomial is irreducible, 0 otherwise.
11
0, 1, 2, 0, 0, 0, 3, 0, 0, 0, 4, 0, 5, 0, 0, 0, 0, 0, 6, 0, 0, 0, 0, 0, 7, 0, 0, 0, 0, 0, 8, 0, 0, 0, 0, 0, 9, 0, 0, 0, 10, 0, 0, 0, 0, 0, 11, 0, 0, 0, 0, 0, 0, 0, 12, 0, 0, 0, 13, 0, 14, 0, 0, 0, 0, 0, 15, 0, 0, 0, 0, 0, 16, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 17, 0, 0, 0, 18, 0, 0, 0, 0, 0, 19, 0
OFFSET
1,3
FORMULA
a(n) = A091225(n) * A091226(n).
CROSSREFS
Inverse of A014580. a(n) = A049084(A091203(n)).
Sequence in context: A325458 A226728 A244140 * A300715 A035444 A376417
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jan 03 2004
STATUS
approved