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A192327
a(n) = prime(n) mod 2*n.
1
0, 3, 5, 7, 1, 1, 3, 3, 5, 9, 9, 13, 15, 15, 17, 21, 25, 25, 29, 31, 31, 35, 37, 41, 47, 49, 49, 51, 51, 53, 3, 3, 5, 3, 9, 7, 9, 11, 11, 13, 15, 13, 19, 17, 17, 15, 23, 31, 31, 29, 29, 31, 29, 35, 37, 39, 41, 39, 41, 41, 39, 45, 55, 55, 53, 53, 63, 65, 71, 69, 69, 71, 75, 77, 79, 79
OFFSET
1,2
LINKS
FORMULA
a(n) = A000040(n) mod (2*n).
EXAMPLE
a(1) = prime(1) mod even(1) = 2 mod 2 = 0.
a(5) = prime(5) mod even(5) = 11 mod 10 = 1.
MAPLE
A192327 := proc(n) modp(ithprime(n), 2*n) ; end proc:
seq(A192327(n), n=1..80) ; # R. J. Mathar, Jul 11 2011
MATHEMATICA
Table[Mod[Prime[n], 2n], {n, 50}] (* Alonso del Arte, Jun 29 2011 *)
PROG
(MATLAB) % n = number of computed terms of sequence
for i=1:n,
a(i) = mod(prime(i), even(i)) ;
end
(PARI) a(n)=prime(n)%(2*n) \\ Charles R Greathouse IV, Jun 29 2011
(Magma) A192327:=func< n | NthPrime(n) mod 2*n >; [ A192327(n): n in [1..80] ]; // Klaus Brockhaus, Jul 10 2011
CROSSREFS
Cf. A004648.
Sequence in context: A031100 A031057 A133069 * A266295 A172049 A021032
KEYWORD
nonn,easy
AUTHOR
Pasi Airikka, Jun 28 2011
STATUS
approved