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A261468
a(n) = prime(n+2) mod prime(n).
0
1, 1, 1, 6, 6, 6, 6, 10, 8, 8, 10, 6, 6, 10, 12, 8, 8, 10, 6, 8, 10, 10, 14, 12, 6, 6, 6, 6, 18, 18, 10, 8, 12, 12, 8, 12, 10, 10, 12, 8, 12, 12, 6, 6, 14, 24, 16, 6, 6, 10, 8, 12, 16, 12, 12, 8, 8, 10, 6, 12, 24, 18, 6, 6, 18, 20, 16, 12, 6, 10, 14, 14, 12
OFFSET
1,4
FORMULA
a(n) = A031131(n) = A075527(n) for n>3. - Alois P. Heinz, Aug 20 2015
EXAMPLE
a(3) = 11 mod 5 = 1.
MATHEMATICA
a[n_]:=PowerMod[Prime[n + 2], 1, Prime[n]]; Table[a[n], {n, 80}] (* Vincenzo Librandi, Aug 20 2015 *)
Mod[#[[3]], #[[1]]]&/@Partition[Prime[Range[80]], 3, 1] (* Harvey P. Dale, Mar 14 2020 *)
PROG
(PARI) first(m)=vector(m, i, prime(i+2)% prime(i)); \\ Anders Hellström, Aug 20 2015
(Magma) [NthPrime(n+2) mod NthPrime(n): n in [1..80]]; // Vincenzo Librandi, Aug 20 2015
CROSSREFS
Cf. A031131.
Sequence in context: A318355 A318237 A201572 * A001734 A342373 A173067
KEYWORD
nonn,easy
AUTHOR
Altug Alkan, Aug 20 2015
STATUS
approved