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A340821
a(n) is the least prime p such that prime(n)*p + prime(n+1)*q + prime(n+2)*r is prime where p,q,r are consecutive primes.
2
3, 3, 3, 61, 3, 3, 17, 3, 5, 13, 3, 29, 17, 13, 3, 5, 7, 19, 23, 5, 11, 3, 3, 23, 3, 3, 3, 19, 19, 7, 7, 23, 43, 5, 7, 67, 7, 7, 11, 19, 29, 3, 3, 7, 19, 5, 3, 3, 23, 3, 29, 7, 17, 13, 37, 13, 7, 3, 23, 3, 3, 19, 53, 29, 17, 3, 3, 43, 7, 43, 5, 11, 5, 7, 19, 19, 19, 163, 3, 3, 3, 7, 5, 31, 17, 19
OFFSET
2,1
LINKS
EXAMPLE
a(3) = 3 where 5*3 + 7*5 + 11*7 = 167 is prime.
MAPLE
f:= proc(n) local k, t;
for k from 1 do
t:=ithprime(n)*ithprime(k) + ithprime(n+1)*ithprime(k+1) + ithprime(n+2)*ithprime(k+2);
if isprime(t) then return ithprime(k) fi;
od
end proc:
map(f, [$2..100]);
CROSSREFS
Cf. A340817.
Sequence in context: A124013 A135584 A174538 * A091323 A174641 A217671
KEYWORD
nonn
AUTHOR
J. M. Bergot and Robert Israel, Jan 22 2021
STATUS
approved