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%I #4 Dec 23 2024 01:56:11
%S 2,23,2357,23581,2358247,235824913,235824916247,
%T 2358249162515829584909,
%U 235824916251582958491829824917162558516292249258249589629182571583855789,2358249162515829584918298249171625585162922492582495896291825715838558298516316558918298250261
%N Prime terms in A287353.
%C Primes Sum_{i=1..k} 10^(k-i)*prime(i) for some k.
%e k prime(k) A287353(k) n a(n)
%e --- -------- ---------- --- -------
%e 1 2 2 1 2
%e 2 3 23 2 23
%e 3 5 235
%e 4 7 2357 3 2357
%e 5 11 23581 4 23581
%e 6 13 235823
%e 7 17 2358247 5 2358247
%o (Python)
%o from sympy import isprime, nextprime
%o m = p = 0
%o while p < 500:
%o p = nextprime(p); m = 10*m + p
%o if isprime(m): print(m, end = ', ')
%Y Cf. A013918, A069151, A287353.
%K nonn
%O 1,1
%A _Ya-Ping Lu_, Dec 22 2024