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%I #16 Aug 25 2014 12:09:28
%S 29,59,79,439,479,659,829,839,859,929,2459,2659,2879,2939,3659,3929,
%T 5479,5639,5659,5839,5879,5939,7459,7639,7829,7879,42829,42839,42859,
%U 42929,42979,45439,45659,45959,45979,47459,47629,47639,47659,47939
%N Primes in which odd positioned digits are composite and even positioned digits are primes. The least significant digit is the taken to be the first digit.
%C Terms are == 9 (mod 10).
%o (PARI) iscomp(n) = (n != 0) && (n != 1) && ! isprime(n);
%o isok(p) = {if (! isprime(p), return (0)); rd = digits(subst(Polrev(digits(p)),x, 10)); for (i=1, #rd, if (i % 2, if (! iscomp(rd[i]), return (0)), if (! isprime(rd[i]), return (0)));); return (1);} \\ _Michel Marcus_, Apr 20 2014
%Y Cf. A083820.
%K base,nonn
%O 1,1
%A _Amarnath Murthy_ and Meenakshi Srikanth (menakan_s(AT)yahoo.com), May 08 2003
%E More terms from _Ray Chandler_, May 20 2003
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