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 A255010 a(n) = A099795(n)^-1 mod prime(n). 3
 1, 2, 3, 2, 1, 10, 7, 15, 20, 1, 14, 19, 11, 23, 6, 11, 45, 42, 37, 34, 10, 29, 76, 77, 14, 71, 12, 88, 40, 22, 30, 75, 115, 59, 110, 14, 113, 154, 13, 154, 142, 40, 50, 25, 71, 16, 11, 18, 91, 174, 138, 35, 115, 38, 27, 195, 206, 113, 75, 119, 181, 111, 203 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS By the definition, a(n)*A099795(n) == 1 (mod prime(n)). a(n) is 1 with the primes 2, 11, 29, 787, 15773 (see A178629). LINKS Umberto Cerruti, Il Teorema Cinese dei Resti (in Italian), 2015. The sequence is on page 21. Eric Weisstein's World of Mathematics, Modular Inverse FORMULA a(n) = A254939(n)/A099795(n). MAPLE with(numtheory): P:=proc(q)  local a, n;  a:=[]; for n from 1 to q do a:=[op(a), n]; if isprime(n+1) then print(lcm(op(a))^(-1) mod (n+1)); fi; od; end: P(10^3); # Paolo P. Lava, Feb 16 2015 MATHEMATICA r[k_] := LCM @@ Range[k]; t[k_] := PowerMod[r[k - 1], -1, k]; Table[t[Prime[n]], {n, 1, 70}] PROG (MAGMA) [Modinv(Lcm([1..p-1]), p): p in PrimesUpTo(400)]; (Sage) [inverse_mod(lcm([1..p-1]), p) for p in primes(400)] (PARI) a(n) = lift(1/Mod(lcm(vector(prime(n)-1, k, k)), prime(n))); \\ Michel Marcus, Feb 13 2015 CROSSREFS Cf. A000040, A099795, A178629, A254924, A254939. Sequence in context: A020858 A090664 A086764 * A292371 A216683 A323326 Adjacent sequences:  A255007 A255008 A255009 * A255011 A255012 A255013 KEYWORD nonn AUTHOR Bruno Berselli, Feb 13 2015 - proposed by Umberto Cerruti (Department of Mathematics "Giuseppe Peano", University of Turin, Italy) STATUS approved

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Last modified January 21 21:30 EST 2020. Contains 331128 sequences. (Running on oeis4.)