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A332733
a(n) is the smallest positive k such that n!*prime(n) + k is a prime.
1
1, 1, 1, 5, 1, 11, 11, 11, 1, 11, 23, 43, 19, 41, 17, 29, 1, 19, 71, 157, 1, 23, 79, 67, 47, 53, 37, 53, 31, 67, 73, 223, 307, 67, 1, 197, 151, 43, 43, 157, 89, 137, 47, 127, 173, 97, 89, 79, 223, 79, 83, 151, 163, 89, 167, 313, 179, 101, 127, 101, 181, 193, 421, 73
OFFSET
1,4
COMMENTS
k equals nextprime(n!*prime(n)) - n!*prime(n).
FORMULA
a(n) = A151800(n!*prime(n)) - n!*prime(n).
MATHEMATICA
spk[n_]:=Module[{c=n!Prime[n]}, NextPrime[c]-c]; Array[spk, 70] (* Harvey P. Dale, Aug 13 2021 *)
PROG
(PARI) a(n) = my(x=n!*prime(n)); nextprime(x+1) - x; \\ Michel Marcus, Feb 22 2020
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved