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a(n) = [(p-1)/2 * (q-1)/2] mod p where p = (n+1)th odd prime, q = n-th odd prime.
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%I #5 Mar 30 2012 17:29:08

%S 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,

%T 28,28,86,99,34,36,105,40,114,41,124,43,45,136,46,146,49,149,150,56,

%U 59,58,58,176,181,61,191,66,199,69,204,71,212,213,76,234,79,79,239,252,86

%N a(n) = [(p-1)/2 * (q-1)/2] mod p where p = (n+1)th odd prime, q = n-th odd prime.

%F a(n) = A087427(n+2) mod p.

%e a(3) = 4 = (5)(3) mod 11; p = 7, q = 5; (p-1)/2 = 5, (q-1)/2 = 3.

%e A087427(5) = 15, A087428(3) = 15 mod 11 = 4.

%K nonn

%O 1,1

%A _Gary W. Adamson_, Sep 01 2003

%E Corrected and extended by _Ray Chandler_, Sep 16 2003