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A106671
a(n) = ( prime(n + 2) * prime(n) - prime(n + 1)^2 ) modulo 3.
1
1, 2, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 1, 1, 1, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 1
OFFSET
1,2
LINKS
FORMULA
a(n) = A056221(n) mod 3 = A010872(A056221(n)). - Michel Marcus, Apr 21 2017
MATHEMATICA
a = Table[Mod[Prime[n + 2]*Prime[n] - Prime[n + 1]^2, 3], {n, 1, 200}]
Mod[#[[3]]#[[1]]-#[[2]]^2, 3]&/@Partition[Prime[Range[110]], 3, 1] (* Harvey P. Dale, Oct 03 2015 *)
PROG
(PARI) a(n) = (prime(n + 2)*prime(n) - prime(n + 1)^2) % 3; \\ Michel Marcus, Apr 21 2017
CROSSREFS
Sequence in context: A093488 A085858 A188172 * A033776 A117371 A117370
KEYWORD
nonn,less
AUTHOR
Roger L. Bagula, May 13 2005
STATUS
approved