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A022458
a(n) = prime(2n-1) mod prime(n).
1
0, 2, 1, 3, 1, 5, 7, 9, 13, 9, 11, 9, 15, 17, 15, 21, 19, 27, 23, 25, 33, 33, 31, 33, 33, 31, 35, 43, 51, 51, 29, 45, 39, 53, 49, 51, 53, 53, 55, 55, 61, 69, 57, 63, 67, 69, 65, 53, 55, 65, 81, 85, 89, 85, 85, 81, 79, 89, 89, 91, 95, 91, 77, 87, 101, 105, 89, 87
OFFSET
1,2
LINKS
MATHEMATICA
Table[Mod[Prime[2n-1], Prime[n]], {n, 70}] (* Harvey P. Dale, Aug 10 2012 *)
PROG
(PARI) for(n=1, 50, print1(prime(2*n-1) % prime(n), ", ")) \\ G. C. Greubel, Feb 28 2018
(Magma) [NthPrime(2*n-1) mod NthPrime(n): n in [1..50]]; // G. C. Greubel, Feb 28 2018
CROSSREFS
Sequence in context: A341865 A347982 A321738 * A377510 A084419 A119606
KEYWORD
nonn
STATUS
approved