%I #17 Sep 08 2022 08:46:01

%S 1,2,4,5,8,9,11,12,15,16,17,18,19,22,26,29,30,33,34,38,39,41,43,45,50,

%T 51,52,54,55,57,60,67,72,73,74,78,79,85,86,87,89,92,93,95,96,97,100,

%U 103,107,108,109,110,111,115,121,123,125,131,134,136,137,141

%N Numbers k such that 90*k + 49 is prime.

%C This sequence was generated by adding 14 Fibonacci-like sequences. Looking at the format 90*k+49 modulo 9 and modulo 10 we see that all entries of A142314 have digital root 2 and last digit 9. (Reverting the process is an application of the Chinese remainder theorem.)

%H Vincenzo Librandi, <a href="/A201818/b201818.txt">Table of n, a(n) for n = 1..10000</a>

%t Select[Range[0, 200], PrimeQ[90 # + 49] &] (* _T. D. Noe_, Dec 06 2011 *)

%o (Magma) [n: n in [0..200] | IsPrime(90*n+49)] // _Vincenzo Librandi_, Dec 11 2011

%o (PARI) is(n)=isprime(90*n+49) \\ _Charles R Greathouse IV_, Feb 17 2017

%K nonn,easy

%O 1,2

%A _J. W. Helkenberg_, Dec 05 2011