A342961 Primes p such that p + the sum of its prime digits is prime.

11, 19, 29, 37, 41, 53, 61, 73, 89, 101, 109, 149, 181, 191, 199, 229, 233, 257, 269, 277, 281, 307, 331, 359, 379, 383, 401, 409, 419, 433, 449, 461, 491, 499, 563, 587, 593, 601, 619, 641, 653, 661, 673, 677, 691, 727, 797, 809, 811, 821, 881, 911, 919, 937, 941, 977, 991, 1009, 1019, 1033

Offset

1,1

Links

Robert Israel, Table of n, a(n) for n = 1..10000

Example

a(3) = 29 is a term because it is prime, the sum of its prime digits is 2, and 29+2 = 31 is also prime.

Maple

f:= p -> p + convert(select(isprime, convert(p, base, 10)), `+`):
select(t -> isprime(t) and isprime(f(t)), [seq(i, i=3..2000, 2)]);

Mathematica

Select[Prime@Range@200, PrimeQ@Total[Join[{#}, Select[IntegerDigits@#, PrimeQ]]]&] (* Giorgos Kalogeropoulos, Apr 01 2021 *)

Prog

(PARI) isok(p) = isprime(p) && isprime(p+sumdigits(p)); \\ Michel Marcus, Apr 01 2021

Crossrefs

Includes A034844. Cf. A085563, A342962.

Sequence in context: A196095 A268271 A053032 * A277123 A034099 A034109

Adjacent sequences: A342958 A342959 A342960 * A342962 A342963 A342964

Keyword

nonn,base

Author

J. M. Bergot and Robert Israel, Mar 31 2021

Status

approved