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%I #12 Aug 15 2014 22:23:44
%S 101,787,34543,7654567,345676543,34567876543
%N Palindromic right-angled primes.
%C Intersection of A002113 and A167842.
%C Intersection of A002385 and A135602.
%C The last term of this sequence is also the last term of A134811.
%e Illustration of a(6) = 34567876543, the last term of this sequence:
%e . . . . . . . . . . .
%e . . . . . 8 . . . . .
%e . . . . 7 . 7 . . . .
%e . . . 6 . . . 6 . . .
%e . . 5 . . . . . 5 . .
%e . 4 . . . . . . . 4 .
%e 3 . . . . . . . . . 3
%e . . . . . . . . . . .
%e . . . . . . . . . . .
%e . . . . . . . . . . .
%o (Python)
%o from sympy import isprime
%o A244369 = []
%o for n in range(1,10):
%o ....for m in range(n-1,-1,-1):
%o ........l = ''.join([str(d) for d in range(n,m-1,-1)])
%o ........p = int(l+l[-2::-1])
%o ........if isprime(p):
%o ............A244369.append(p)
%o ....for m in range(n+1,10):
%o ........l = ''.join([str(d) for d in range(n,m+1)])
%o ........p = int(l+l[-2::-1])
%o ........if isprime(p):
%o ............A244369.append(p)
%o A244369 = sorted(A244369) # _Chai Wah Wu_, Aug 15 2014
%Y Cf. A000040, A002113, A002385, A134811, A135602, A167842.
%K nonn,base,fini,full
%O 1,1
%A _Omar E. Pol_, Jun 26 2014
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