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A087900
2*3*5*6*...*a(n) -+ 1 are primes, with a(n+1) > a(n).
2
2, 3, 5, 6, 9, 13, 22, 24, 51, 92, 120, 176, 258, 274, 375, 663, 713, 760, 911, 1002, 1155, 1356, 1455, 1502, 1628, 1701, 1867, 2630, 3212, 4858, 4892, 6282, 7507, 8214, 8897, 9348, 9876, 11287, 13296, 14299, 15964, 17642, 18303, 18599, 22310, 23495, 24101, 25513
OFFSET
1,1
COMMENTS
Recursive twin-prime generating sequence.
For the twin primes so generated see A087901.
REFERENCES
H. Dubner, "Recursive Prime Generating Sequences", Table 6 pp. 175 Journal of Recreational Mathematics 29(3)1998 Baywood NY.
LINKS
MAPLE
R:= 2; s:= 2: count:= 1:
for r from 3 while count < 100 do
if isprime(s*r+1) and isprime(s*r-1) then
count:= count+1; R:= R, r; s:= s*r;
fi;
od:
R; # Robert Israel, Jun 11 2025
CROSSREFS
Sequence in context: A240726 A240203 A018126 * A101216 A371685 A175095
KEYWORD
nonn
AUTHOR
Lekraj Beedassy, Oct 14 2003
STATUS
approved