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A236437
Primes which occur in their proper place in A236174.
5
2, 263, 269, 347, 397, 431, 461, 479, 499, 569, 599, 607, 677, 683, 719, 769, 797, 821, 929, 941, 1019, 1031, 1049, 1051, 1061, 1069, 1103, 1181, 1223, 1229, 1237, 1297, 1307, 1367, 1399, 1409, 1439, 1453, 1487, 1489, 1523, 1553, 1559, 1571, 1619, 1637, 1733, 1759, 1811, 1823, 1949, 1973, 1997
OFFSET
1,1
COMMENTS
Primes p such that A236174(k) = prime(k) for some k. The values of k are (essentially) given in A235377.
Same as A052033 if the initial 2 is omitted.
EXAMPLE
263 is the 56th prime and is also the 56th term in A236174.
PROG
(Python)
from sympy import prime, isprime
def A236174(n):
....p = prime(n)
....for b in range(2, 11):
........x, y, z = p, 0, 1
........while x >= b:
............x, r = divmod(x, b)
............y += r*z
............z *= 10
........y += x*z
........if isprime(y):
............return y
A236437_list = [prime(n) for n in range(1, 10**6) if A236174(n) == prime(n)]
# Chai Wah Wu, Jan 03 2015
CROSSREFS
KEYWORD
nonn,base
AUTHOR
N. J. A. Sloane, Jan 25 2014
STATUS
approved