A158614 Numbers n such that 30*n + 11 is prime.

0, 1, 2, 3, 4, 6, 8, 9, 10, 13, 14, 15, 16, 17, 21, 23, 25, 27, 29, 30, 31, 32, 34, 35, 36, 38, 39, 43, 45, 48, 49, 50, 52, 53, 57, 60, 62, 63, 64, 69, 70, 71, 78, 79, 80, 81, 84, 86, 87, 90, 91, 93, 95, 100, 101, 106, 107, 108, 112, 115, 116, 119, 122, 123, 125, 127, 128

Offset

1,3

Comments

Encoded primes with LSD 1 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 of the quotient is in the sequence, the number is prime.

Links

Ivan Neretin, Table of n, a(n) for n = 1..10000

Formula

a(n) = (A132232(n) - 11)/30 = floor(A132232(n)/30). - Ray Chandler, Apr 07 2009

Example

Example: 3191, with LSD 1 and (SOD-1)/3 = 4.33 (non-integer); Then 3191/30=106.367, or 106 which is in the sequence, thus 3191 is prime.

Mathematica

Select[Range[0, 130], PrimeQ[30#+11]&] (* Harvey P. Dale, Jul 26 2011 *)

Prog

(PARI) is(n)=isprime(30*n+11) \\ Charles R Greathouse IV, Feb 17 2017

Crossrefs

Cf. A111175, A158573, A158648, A158746, A158791, A158806, A158850.

Sequence in context: A002183 A349607 A060306 * A303434 A362399 A080823

Adjacent sequences: A158611 A158612 A158613 * A158615 A158616 A158617

Keyword

nonn

Author

Ki Punches, Mar 22 2009, Mar 29 2009

Extensions

Edited by Ray Chandler, Apr 07 2009

Status

approved