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A065861 Remainder when the n-th composite number is divided by pi(n), the number of primes not exceeding n. 2
0, 0, 1, 1, 0, 2, 3, 0, 2, 0, 1, 4, 0, 1, 2, 6, 0, 6, 0, 1, 2, 8, 0, 2, 3, 4, 6, 4, 5, 2, 4, 5, 6, 7, 8, 6, 7, 8, 9, 6, 8, 6, 7, 8, 9, 6, 8, 9, 10, 12, 14, 11, 12, 13, 14, 0, 1, 14, 16, 13, 14, 15, 16, 0, 1, 16, 17, 18, 0, 16, 18, 15, 16, 18, 20, 0, 1, 20, 0, 1, 2, 22, 0, 1, 2, 3, 4, 0, 1, 2, 3, 4 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,6

LINKS

Harry J. Smith, Table of n, a(n) for n = 2..1000

FORMULA

a(n) = A002808(n) mod A000720(n).

EXAMPLE

n=100, c(100)=133, pi(100)=25, a(100)=8 because 133 = 5*25 + 8.

PROG

(PARI) Composite(n) = { local(k); k=n + primepi(n) + 1; while (k != n + primepi(k) + 1, k = n + primepi(k) + 1); return(k) } { for (n = 2, 1000, a=Composite(n)%primepi(n); write("b065861.txt", n, " ", a) ) } \\ Harry J. Smith, Nov 02 2009

CROSSREFS

Cf. A002808, A000720, A065855-A065864.

Sequence in context: A322147 A059066 A059067 * A126832 A068908 A226192

Adjacent sequences:  A065858 A065859 A065860 * A065862 A065863 A065864

KEYWORD

nonn

AUTHOR

Labos Elemer, Nov 26 2001

STATUS

approved

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Last modified April 18 22:08 EDT 2019. Contains 322237 sequences. (Running on oeis4.)