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A087901
Twin primes associated with A087900.
2
5, 7, 29, 31, 179, 181, 1619, 1621, 21059, 21061, 463319, 463321, 11119679, 11119681, 567103679, 567103681, 52173538559, 52173538561, 6260824627199, 6260824627201, 1101905134387199, 1101905134387201, 284291524671897599, 284291524671897601, 77895877760099942399, 77895877760099942401
OFFSET
1,1
LINKS
FORMULA
From Robert Israel, Jun 11 2025: (Start)
a(2*n-1) = (Product_{i=1..n+1} A087900(i)) - 1.
a(2*n) = (Product_{i=1..n+1} A087900(i)) + 1. (End)
MAPLE
R:= NULL; s:= 2: count:= 0:
for r from 3 while count < 30 do
if isprime(s*r+1) and isprime(s*r-1) then
count:= count+2; s:= s*r; R:= R, s-1, s+1;
fi;
od:
R; # Robert Israel, Jun 11 2025
CROSSREFS
Cf. A087900.
Sequence in context: A266078 A147993 A213901 * A018776 A104683 A153121
KEYWORD
nonn,tabf
AUTHOR
Lekraj Beedassy, Oct 14 2003
STATUS
approved