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A196007 Numbers n such that 90n + 83 is prime.

%I A196007 #21 May 02 2017 18:58:32
%S A196007 0,1,2,3,4,10,12,15,16,17,21,22,23,24,25,26,29,32,36,37,39,42,45,49,
%T A196007 50,51,54,58,59,60,61,64,67,68,71,72,73,75,77,78,79,80,84,86,89,91,92,
%U A196007 94,101,105,106,108,112,113,114,115,117,120
%N A196007 Numbers n such that 90n + 83 is prime.
%H A196007 Ivan Neretin, <a href="/A196007/b196007.txt">Table of n, a(n) for n = 1..10000</a>
%F A196007 a(n) = (A142332(n)-83)/90.
%p A196007 A142332 := proc(n)
%p A196007         option remember;
%p A196007         if n = 1 then
%p A196007                 83 ;
%p A196007         else
%p A196007                 a := nextprime(procname(n-1)) ;
%p A196007                 while (a mod 45) <> 38 do
%p A196007                         a := nextprime(a) ;
%p A196007                 end do;
%p A196007                 return a;
%p A196007         end if;
%p A196007 end proc:
%p A196007 A196007 := proc(n)
%p A196007         (A142332(n)-83)/90 ;
%p A196007 end proc:
%p A196007 seq(A196007(n),n=1..80) ; # _R. J. Mathar_, Oct 31 2011
%t A196007 Select[Range[0, 120], PrimeQ[90 # + 83] &] (* _Ivan Neretin_, May 02 2017 *)
%o A196007 (PARI) is(n)=isprime(90*n+83) \\ _Charles R Greathouse IV_, Jul 12 2016
%Y A196007 Cf. A196000, A198382, A181732, A195993. These are digital root and last digit preserving sequences.
%K A196007 nonn,easy
%O A196007 1,3
%A A196007 _J. W. Helkenberg_, Oct 27 2011