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Numbers n such that 30*n + 29 is prime.
8

%I #8 Feb 17 2017 16:48:20

%S 0,1,2,4,5,7,8,11,12,13,14,15,16,18,19,21,23,26,27,30,33,34,36,40,41,

%T 42,43,46,47,49,51,53,56,62,64,65,67,68,69,70,76,77,79,81,84,85,86,89,

%U 90,92,93,95,96,97,98,99,102,103,106,109,110,111,112,114,117,121,123,125

%N Numbers n such that 30*n + 29 is prime.

%C Encoded primes with LSD 9 and (SOD-1)/3 non-integer, (LSD, least significant digit; SOD, sum of digits). Divide any such number by 30, if the whole number portion from the quotient is in the sequence, the number is prime.

%F a(n) = (A132236(n) - 29)/30 = Floor[A132236(n)/30]. - Chandler

%e Example: 3209 with LSD 9 and (SOD-1)/3 non-integer; Then 3209/30 = 106.966, or 106, which is in the sequence, thus 3209 is prime.

%o (PARI) is(n)=isprime(30*n+29) \\ _Charles R Greathouse IV_, Feb 17 2017

%Y Cf. A111175, A158573, A158614, A158648, A158746, A158791, A158806.

%K nonn

%O 1,3

%A _Ki Punches_, Mar 28 2009

%E Edited by _Ray Chandler_, Apr 07 2009