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A379426
Prime terms in A287353.
0
2, 23, 2357, 23581, 2358247, 235824913, 235824916247, 2358249162515829584909, 235824916251582958491829824917162558516292249258249589629182571583855789, 2358249162515829584918298249171625585162922492582495896291825715838558298516316558918298250261
OFFSET
1,1
COMMENTS
Primes Sum_{i=1..k} 10^(k-i)*prime(i) for some k.
EXAMPLE
k prime(k) A287353(k) n a(n)
--- -------- ---------- --- -------
1 2 2 1 2
2 3 23 2 23
3 5 235
4 7 2357 3 2357
5 11 23581 4 23581
6 13 235823
7 17 2358247 5 2358247
PROG
(Python)
from sympy import isprime, nextprime
m = p = 0
while p < 500:
p = nextprime(p); m = 10*m + p
if isprime(m): print(m, end = ', ')
CROSSREFS
KEYWORD
nonn
AUTHOR
Ya-Ping Lu, Dec 22 2024
STATUS
approved