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A065863
Remainder when n-th prime is divided by the number of nonprimes not exceeding n.
3
0, 0, 0, 1, 1, 1, 2, 3, 3, 5, 1, 2, 6, 3, 2, 3, 9, 6, 1, 11, 8, 9, 13, 14, 1, 16, 13, 12, 14, 13, 7, 5, 5, 1, 5, 1, 7, 7, 5, 5, 11, 7, 17, 13, 11, 7, 19, 25, 23, 19, 17, 17, 19, 23, 23, 23, 23, 19, 25, 23, 25, 29, 37, 35, 31, 29, 43, 43, 47, 43, 47, 47, 3, 2, 1, 53, 53, 55, 2, 3, 6, 1, 11, 6
OFFSET
1,7
LINKS
FORMULA
a(n) = prime(n) mod (n - pi(n)) = A000040(n) mod A062298(n).
EXAMPLE
n=25, p(25)=97, n - pi(n) = 25 - 9 = 16, a(25)=1 because 97 = 6*16 + 1.
MATHEMATICA
Table[Mod[Prime[n], n-PrimePi[n]], {n, 90}] (* Harvey P. Dale, Aug 04 2015 *)
PROG
(PARI) { for (n = 1, 1000, a=prime(n)%(n - primepi(n)); write("b065863.txt", n, " ", a) ) } \\ Harry J. Smith, Nov 02 2009
KEYWORD
nonn
AUTHOR
Labos Elemer, Nov 26 2001
STATUS
approved