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A175802
a(n) = 2^(positive nonprime(n)-1) mod (positive nonprime(n+1)).
1
1, 2, 0, 2, 6, 8, 4, 2, 0, 8, 12, 2, 12, 8, 8, 14, 20, 4, 8, 0, 2, 18, 22, 16, 10, 2, 24, 8, 24, 38, 24, 32, 32, 6, 2, 4, 44, 5, 8, 2, 30, 32, 16, 2, 0, 8, 16, 36, 2, 46, 8, 56, 17, 4, 43, 16, 32, 20, 42, 8, 8, 44, 2, 64, 8, 32, 4, 2, 48, 27, 64, 88, 2, 44, 8, 32, 23, 54, 44, 18
OFFSET
1,2
FORMULA
a(n) = 2^(A018252(n)-1) mod A018252(n+1).
EXAMPLE
a(4)=2 because 2^(A018252(4)-1) = 2^7 = 128 mod A018252(4+1) = 10.
MAPLE
A175802 := proc(n) local n1, n2 ; n1 := A018252(n) ; n2 := A018252(n+1) ; (2^(n1-1)) mod n2 ; end proc: # R. J. Mathar, Dec 05 2010
CROSSREFS
Cf. A018252.
Sequence in context: A156815 A303439 A303345 * A161803 A057980 A242840
KEYWORD
nonn,less
AUTHOR
EXTENSIONS
Corrected by R. J. Mathar, Dec 05 2010
STATUS
approved