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A104301
Primes which are the reverse concatenation of two consecutive square numbers.
5
41, 6449, 196169, 576529, 11561089, 14441369, 27042601, 38443721, 51845041, 60845929, 67246561, 84648281, 1081610609, 2073620449, 2190421609, 2822427889, 3240032041, 4000039601, 4326442849, 5017649729, 5290052441, 6250062001
OFFSET
1,1
EXAMPLE
The first term is 41 which is a prime and is the reverse concatenation of 1 and 4 which are two consecutive square numbers.
PROG
(Python)
from sympy import isprime
A104301_list = []
for n in range(1, 2000):
....x = int(str((n+1)**2)+str(n**2))
....if isprime(x):
........A104301_list.append(x) # Chai Wah Wu, Sep 13 2014
CROSSREFS
These are the primes in A246972.
Cf. A104242.
Sequence in context: A091758 A208255 A221325 * A221300 A221377 A160477
KEYWORD
base,nonn
AUTHOR
Shyam Sunder Gupta, Apr 17 2005
STATUS
approved