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A087900 2*3*5*6*...*a(n) -+ 1 are primes, with a(n+1) > a(n).

%I A087900 #12 Jun 11 2025 18:37:48
%S A087900 2,3,5,6,9,13,22,24,51,92,120,176,258,274,375,663,713,760,911,1002,
%T A087900 1155,1356,1455,1502,1628,1701,1867,2630,3212,4858,4892,6282,7507,
%U A087900 8214,8897,9348,9876,11287,13296,14299,15964,17642,18303,18599,22310,23495,24101,25513
%N A087900 2*3*5*6*...*a(n) -+ 1 are primes, with a(n+1) > a(n).
%C A087900 Recursive twin-prime generating sequence.
%C A087900 For the twin primes so generated see A087901.
%D A087900 H. Dubner, "Recursive Prime Generating Sequences", Table 6 pp. 175 Journal of Recreational Mathematics 29(3)1998 Baywood NY.
%H A087900 Robert Israel, <a href="/A087900/b087900.txt">Table of n, a(n) for n = 1..210</a>
%p A087900 R:= 2; s:= 2: count:= 1:
%p A087900 for r from 3 while count < 100 do
%p A087900     if isprime(s*r+1) and isprime(s*r-1) then
%p A087900       count:= count+1; R:= R,r; s:= s*r;
%p A087900     fi;
%p A087900 od:
%p A087900 R; # _Robert Israel_, Jun 11 2025
%Y A087900 Cf. A036014, A087901.
%K A087900 nonn
%O A087900 1,1
%A A087900 _Lekraj Beedassy_, Oct 14 2003