A254925 The slowest increasing sequence of primes such that no three terms sum up to a prime number.

3, 5, 7, 83, 317, 383, 2111, 2423, 3797, 8117, 12143, 18959, 24077, 33311, 89561, 142979, 161309, 191339, 218531, 234629, 278981, 297263, 516911, 731957, 746777, 882029, 908627, 953789, 1245551, 1279361, 1790339, 2550059, 2638667

Offset

1,1

Comments

Start with s={3,5,7}. Then a(n) is the least prime > a(n-1) such that no three terms sum up to a prime number.

Links

Zak Seidov, Table of n, a(n) for n = 1..104

Mathematica

s = {3, 5, 7}; bs = {8, 10, 12}; p = 7; Do[Label[np]; p = NextPrime[p];
Do[If[PrimeQ[p + bs[[k]]], Goto[np]], {k, Length[bs]}]; AppendTo[s, p]; bs = Join[bs, s + p]; Print[p], {100}]

Crossrefs

Sequence in context: A056145 A119939 A306573 * A153138 A201270 A160360

Adjacent sequences: A254922 A254923 A254924 * A254926 A254927 A254928

Keyword

nonn

Author

Zak Seidov, Feb 10 2015

Status

approved