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A245097 Number of primes greater than n and not greater than the smallest pseudoprime to base n. 1
2, 67, 22, 4, 27, 8, 5, 0, 5, 7, 1, 13, 2, 0, 62, 9, 7, 2, 6, 0, 8, 11, 2, 0, 0, 0, 9, 5, 1, 5, 4, 0, 12, 0, 4, 13, 2, 0, 12, 12, 14, 33, 7, 0, 7, 18, 3, 0, 3, 0, 3, 8, 2, 0, 2, 0, 2, 16, 6, 51, 6, 0, 50, 0, 11, 6, 4, 0, 4, 20, 7, 3, 8, 0, 3, 0, 32, 47, 2, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
FORMULA
a(n) = Sum {k=n+1..A007535(n)} A010051(k).
a(n) = A000720(A007535(n)) - A000720(n).
PROG
(Haskell)
a245097 n = sum $ map a010051' [n + 1 .. a007535 n]
(PARI) f(n) = forcomposite(m=n+1, , if(Mod(n, m)^(m-1)==1, return(m))); \\ A007535
a(n) = primepi(f(n)) - primepi(n); \\ Michel Marcus, Jan 24 2022
CROSSREFS
Sequence in context: A119552 A230663 A016535 * A139864 A107993 A131604
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Nov 12 2014
STATUS
approved

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Last modified March 28 07:48 EDT 2024. Contains 371235 sequences. (Running on oeis4.)