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 A324657 a(n) is the number of successive primorials A002110(i) larger than prime(n) that need to be tried before sum prime(n)+A002110(i) is found to be composite. 3
 0, 0, 1, 1, 1, 2, 2, 0, 3, 4, 2, 0, 5, 0, 2, 1, 1, 3, 3, 2, 5, 0, 3, 0, 1, 2, 1, 4, 0, 0, 2, 0, 2, 1, 2, 0, 3, 2, 0, 1, 1, 0, 1, 0, 0, 1, 2, 0, 0, 2, 1, 2, 3, 0, 0, 0, 1, 0, 0, 1, 4, 0, 1, 2, 0, 0, 0, 4, 1, 1, 1, 0, 1, 2, 1, 1, 1, 3, 2, 1, 2, 1, 1, 0, 2, 1, 0, 1, 0, 0, 2, 4, 2, 1, 0, 0, 3, 0, 4, 1, 3, 0, 0, 1, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,6 COMMENTS See comments and examples in A324656. LINKS Antti Karttunen, Table of n, a(n) for n = 1..25000 FORMULA a(n) = A324656(A000040(n)). PROG (PARI) A002110(n) = prod(i=1, n, prime(i)); A235224(n, p=2) = if(!n, n, 1+A235224(n\p, nextprime(p+1))); A324656(n) = { my(k=0, b=A235224(n)); while(isprime(n+A002110(b+k)), k++); (k); }; A324657(n) = A324656(prime(n)); CROSSREFS Cf. A000040, A002110, A324656. Sequence in context: A262879 A336889 A278482 * A339422 A094053 A294598 Adjacent sequences:  A324654 A324655 A324656 * A324658 A324659 A324660 KEYWORD nonn AUTHOR Antti Karttunen, Mar 11 2019 STATUS approved

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Last modified September 17 03:42 EDT 2021. Contains 347478 sequences. (Running on oeis4.)