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Primes which are the reverse concatenation of two consecutive square numbers.
5

%I #9 Sep 14 2014 00:20:48

%S 41,6449,196169,576529,11561089,14441369,27042601,38443721,51845041,

%T 60845929,67246561,84648281,1081610609,2073620449,2190421609,

%U 2822427889,3240032041,4000039601,4326442849,5017649729,5290052441,6250062001

%N Primes which are the reverse concatenation of two consecutive square numbers.

%e The first term is 41 which is a prime and is the reverse concatenation of 1 and 4 which are two consecutive square numbers.

%o (Python)

%o from sympy import isprime

%o A104301_list = []

%o for n in range(1,2000):

%o ....x = int(str((n+1)**2)+str(n**2))

%o ....if isprime(x):

%o ........A104301_list.append(x) # _Chai Wah Wu_, Sep 13 2014

%Y These are the primes in A246972.

%Y Cf. A104242.

%K base,nonn

%O 1,1

%A _Shyam Sunder Gupta_, Apr 17 2005