A243623 Prime terms in A214829.

7, 29, 1087, 1999, 3677, 6763, 5487349608898607, 115507410616162687, 878001744429057971864287, 210582098197038415344728317608265501, 870277059555114378903885645581650740066907

Offset: 1

Author

Robert Price, Jun 07 2014

Keywords

• nonn

Comments

a(12) has 114 digits and thus is too large to display here. It corresponds to A214829(426).

Links

• Robert Israel, Table of n, a(n) for n = 1..20

Crossrefs

Cf. A001590, A100683, A231574, A231575, A232543, A214899, A020992, A233554. A214727, A234696, A141523, A235862,A214825, A235873, A214827, A242324, A214827, A214828, A214829, A242572, A242576, A243622.

Programs

Maple

f:= gfun:-rectoproc({a(n) = a(n-1) + a(n-2) + a(n-3), a(0) = 1, a(1) = 7, a(2) = 7},a(n),remember):
select(isprime, map(f, [$2..1000])); # Robert Israel, Sep 02 2024

Mathematica

a={1,7,7}; Print["7"]; Print["7"]; For[n=3, n<=1000, n++, sum=Plus@@a; If[PrimeQ[sum], Print[sum]]; a=RotateLeft[a]; a[[3]]=sum]

Extensions

7 inserted as a(1) by Robert Israel, Sep 02 2024