OFFSET
1,1
COMMENTS
a(n) is the first k such that the sum of primes, with repetition, dividing (k+n-1)!/(k-1)! is prime.
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
MAPLE
sopf:= proc(n) option remember; local t; add(t[1]*t[2], t=ifactors(n)[2]) end proc:
f:= proc(n) local j, t, i;
t:= add(sopf(i), i=1..n);
for j from 1 do
if isprime(t) then return j fi;
t:= t + sopf(j+n)-sopf(j)
od
end proc:
map(f, [$1..100]);
CROSSREFS
KEYWORD
nonn
AUTHOR
J. M. Bergot and Robert Israel, Apr 07 2021
STATUS
approved