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A235267
Places n such that 1 + q!/p! is prime, where p = prime(n) and q = prime(n + 1).
1
3, 5, 33, 35, 43, 69, 86, 106, 108, 116, 124, 127, 171, 174, 182, 200, 201, 238, 255, 256, 270, 271, 277, 294, 310, 318, 323, 332, 356, 384, 388, 390, 392, 397, 398, 402, 409, 469, 494, 495, 520, 542, 551, 562, 572, 582, 606, 632, 633, 645, 649, 652, 671, 672
OFFSET
1,1
LINKS
EXAMPLE
3 is in the sequence because (prime(3)! + prime(4)!)/prime(3)! = (5! + 7!)/5! = (120 + 5040)/120 = 43 which is prime.
MAPLE
isA235267 := proc(n)
local p, q ;
p := ithprime(n) ;
q := nextprime(p) ;
if isprime(1+q!/p!) then
true;
else
false;
end if;
end proc:
for n from 1 do
if isA235267(n) then
print(n) ;
end if;
end do:
CROSSREFS
Sequence in context: A179387 A295364 A199774 * A284379 A372718 A103010
KEYWORD
nonn
AUTHOR
K. D. Bajpai, Jan 05 2014
STATUS
approved