

A158746


Numbers n such that 30*n + 13 is prime.


8



0, 1, 2, 3, 5, 6, 7, 9, 10, 12, 14, 15, 17, 20, 21, 22, 24, 27, 28, 29, 34, 35, 36, 37, 38, 40, 43, 47, 48, 49, 51, 55, 56, 57, 58, 59, 62, 64, 66, 68, 69, 70, 71, 73, 76, 79, 82, 83, 86, 89, 90, 93, 94, 98, 105, 108, 110, 111, 112, 114, 115, 119, 120, 121, 122, 124, 126, 127
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OFFSET

1,3


COMMENTS

Encoded primes with LSD 3, (SOD1)/3 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

Table of n, a(n) for n=1..68.


FORMULA

a(n) = (A132233(n)  13)/30 = Floor[A132233(n)/30].  Chandler


EXAMPLE

Example: 3163, with LSD 3 and (SOD1)/3 = 4 (integer); Then 3163/30 = 105.433, or 105 which is in the sequence, thus 3163 is prime.


MATHEMATICA

Select[Range[0, 200], PrimeQ[30#+13]&] (* Harvey P. Dale, Oct 16 2018 *)


PROG

(PARI) is(n)=isprime(30*n+13) \\ Charles R Greathouse IV, Feb 17 2017


CROSSREFS

Cf. A111175, A158573, A158614, A158648, A158791, A158806, A158850.
Sequence in context: A248229 A207672 A038161 * A062470 A179460 A171886
Adjacent sequences: A158743 A158744 A158745 * A158747 A158748 A158749


KEYWORD

nonn


AUTHOR

Ki Punches, Mar 25 2009


EXTENSIONS

Edited by Ray Chandler, Apr 07 2009


STATUS

approved



