A202105 - OEIS

%I #12 Feb 17 2017 14:53:11

%S 0,2,3,7,9,11,12,13,14,16,18,19,21,23,24,25,26,27,31,37,38,40,41,42,

%T 44,45,47,48,52,53,54,55,60,62,67,68,70,74,75,76,80,81,84,87,88,89,91,

%U 98,100,101,104,114,118,119,123,126,130,131,132,137,139,142

%N Numbers n such that 90*n + 43 is prime.

%C This sequence was generated by adding 12 Fibonacci-like sequences [See: PROG]. Looking at the format 90n+43 modulo 9 and modulo 10 we see that all entries of A142334 have digital root 7 and last digit 3. (Reverting the process is an application of the Chinese remainder theorem.) The 12 Fibonacci-like sequences are generated (via the p and q values given in the PERL program) from the base p,q pairs 43*91, 19*7, 37*79, 73*61, 11*53, 29*17, 47*89, 83*71, 13*31, 49*67, 23*41, 59*77.

%t Select[Range[0, 200], PrimeQ[90 # + 43] &]

%o (PARI) is(n)=isprime(90*n+43) \\ _Charles R Greathouse IV_, Feb 17 2017

%Y Cf. A181732, A198382, A195993, A196000, A196007, A201739, A201734, A201804, A201816, A201817, A201818, A201820, A201822, A202101, A202104.

%K easy,nonn

%O 1,2

%A _J. W. Helkenberg_, Dec 11 2011