A283622 a(n) = smallest k > n + 1 not of the form p + n^x with p prime, where gcd(k, n) = 1 and gcd(k-1, n-1) = 1.

127, 328, 149, 26, 127, 254, 17, 34, 59, 50, 37, 134, 23, 136, 65, 26, 43, 96, 29, 142, 47, 50, 49, 116, 35, 52, 53, 56, 79, 122, 41, 58, 59, 92, 157, 86, 47, 64, 89, 50, 67, 186, 53, 94, 95, 56, 73, 134, 59, 100, 77, 78, 79, 146, 65, 82, 83, 86, 109, 204, 71

Offset

2,1

Links

Table of n, a(n) for n=2..62.

Prog

(Magma) lst:=[]; for n in [2..62] do k:=n+2; t:=0; while t eq 0 do if GCD(k, n) eq 1 and GCD(k-1, n-1) eq 1 then x:=-1; repeat x+:=1; p:=k-n^x; until p lt 2 or IsPrime(p); if p lt 2 then Append(~lst, k); t:=1; end if; end if; k+:=1; end while; end for; lst;

Crossrefs

Cf. A006285, A282430.

Sequence in context: A157949 A142165 A031933 * A080035 A162004 A112419

Adjacent sequences: A283619 A283620 A283621 * A283623 A283624 A283625

Keyword

nonn

Author

Arkadiusz Wesolowski, Mar 12 2017

Status

approved