cp's OEIS Frontend

A381878 Prime numbers p such that the sum of the d_i-th prime numbers, where (d_i) are the nonzero digits of p, is also a prime.

%I A381878 #15 Mar 19 2025 10:30:26
%S A381878 2,3,5,7,13,17,31,71,103,107,181,211,223,227,229,233,239,257,277,293,
%T A381878 347,383,389,433,443,449,467,479,487,499,523,563,569,587,647,653,659,
%U A381878 677,683,701,727,743,769,787,811,839,857,859,863,877,883,947,967,983
%N A381878 Prime numbers p such that the sum of the d_i-th prime numbers, where (d_i) are the nonzero digits of p, is also a prime.
%e A381878 13 is a term, because prime(1) + prime(3) = 2 + 5 = 7 is prime.
%t A381878 Select[Prime[Range[170]], PrimeQ[Total[Prime[DeleteCases[IntegerDigits[#],0]]]] &] (* _Stefano Spezia_, Mar 09 2025 *)
%o A381878 (Python)
%o A381878 from sympy import isprime, prime
%o A381878 def ok(p): return isprime(p) and isprime(sum(prime(di) for di in map(int, str(p)) if di))
%o A381878 print([k for k in range(1, 999) if ok(k)]) # _Michael S. Branicky_, Mar 09 2025
%Y A381878 Cf. A046704, A052034.
%K A381878 nonn,base,less
%O A381878 1,1
%A A381878 _Jean-Marc Rebert_, Mar 09 2025