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A087428
a(n) = [(p-1)/2 * (q-1)/2] mod p where p = (n+1)th odd prime, q = n-th odd prime.
2
2, 6, 4, 4, 14, 15, 7, 9, 24, 11, 32, 33, 13, 15, 46, 16, 52, 19, 19, 61, 22, 24, 75, 77, 78, 28, 28, 86, 99, 34, 36, 105, 40, 114, 41, 124, 43, 45, 136, 46, 146, 49, 149, 150, 56, 59, 58, 58, 176, 181, 61, 191, 66, 199, 69, 204, 71, 212, 213, 76, 234, 79, 79, 239, 252, 86
OFFSET
1,1
FORMULA
a(n) = A087427(n+2) mod p.
EXAMPLE
a(3) = 4 = (5)(3) mod 11; p = 7, q = 5; (p-1)/2 = 5, (q-1)/2 = 3.
A087427(5) = 15, A087428(3) = 15 mod 11 = 4.
CROSSREFS
Sequence in context: A003077 A323482 A057143 * A115508 A348669 A195730
KEYWORD
nonn
AUTHOR
Gary W. Adamson, Sep 01 2003
EXTENSIONS
Corrected and extended by Ray Chandler, Sep 16 2003
STATUS
approved