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 A097445 Second occurrence where n# - p is prime for primes p = 3, 5, ... 0
 19, 197, 2293, 30011, 510463, 9699653, 223092809, 6469693163, 200560490051, 7420738134703, 304250263527157, 13082761331669881, 614889782588491313, 32589158477190044641, 1922760350154212638961, 117288381359406970983047 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,1 COMMENTS Care has to be taken to start with a large enough n to be sure terms are not missed. This was for n=100. This and A097444 were difficult to obtain using PARI. LINKS Table of n, a(n) for n=2..17. FORMULA n# is n primorial = product of primes 2*3*5*...*p <= n. EXAMPLE 3# = 2*3 = 6. 6 - 3 = 3 (first prime), 6 - 5 = 1, not prime, thus 3# - p is omitted. 5# = 2*3*5 = 30. 30 - 7 = 23 (first prime), 30 - 11 = 19 (second prime). PROG (PARI) primorm2(n) = { pr=1; for(x=1, n, f=1; pr*=prime(x); for(m=1, n, y=pr-prime(m); if(isprime(y), f=1; for(m=m+1, n, y=pr-prime(m); if(isprime(y), print1(y", "); f=0; break, f=1)); ); if(f==0, break) ) ) } CROSSREFS Sequence in context: A048556 A141995 A210339 * A238697 A256639 A058370 Adjacent sequences: A097442 A097443 A097444 * A097446 A097447 A097448 KEYWORD nonn AUTHOR Cino Hilliard, Aug 23 2004 STATUS approved

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Last modified June 2 10:25 EDT 2023. Contains 363097 sequences. (Running on oeis4.)