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A246872
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Lesser of Gridgeman pairs in base 16 in increasing order: pairs of primes palindromic in base 16 which differ only in their middle digits by a difference of 1.
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3
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2, 337, 433, 1831, 2377, 3373, 3517, 104593, 209203, 229507, 236947, 244147, 253651, 332053, 337957, 341557, 350293, 361093, 376501, 477511, 486247, 488311, 489847, 497047, 592393, 633001, 639433, 744283, 745051, 766651, 885133, 894637, 906973, 911341, 914941
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OFFSET
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1,1
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LINKS
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EXAMPLE
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433 and 449 are 2 primes which are 1B1 and 1C1 in hexadecimal notation.
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PROG
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(Python)
from gmpy2 import digits
from sympy import isprime
for n in range(1, 16**4):
....s1 = digits(n, 16)
....s2 = s1[::-1]
....for m in range(15):
........p1, p2 = int(s1+digits(m, 16)+s2, 16), int(s1+digits(m+1, 16)+s2, 16)
........if isprime(p1) and isprime(p2):
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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