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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..22.

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

Adjacent sequences:  A104298 A104299 A104300 * A104302 A104303 A104304

KEYWORD

base,nonn

AUTHOR

Shyam Sunder Gupta, Apr 17 2005

STATUS

approved

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Last modified July 20 16:34 EDT 2019. Contains 325185 sequences. (Running on oeis4.)