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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

Index entries for sequences related to primorial numbers

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.)