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A173683 revision #22

A173683

Sum of n mod p, for p = 2, 3, 5, ..., smallest prime >= n.

1, 0, 1, 5, 3, 7, 4, 14, 16, 14, 8, 20, 13, 24, 23, 28, 18, 38, 27, 48, 47, 43, 29, 57, 62, 57, 64, 65, 46, 76, 56, 97, 95, 88, 88, 95, 70, 99, 96, 102, 74, 117, 88, 133, 140, 130, 98, 156, 165, 174, 170, 171, 134, 199, 200, 208, 203, 189, 147, 214

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,4

LINKS

Alois P. Heinz, Table of n, a(n) for n = 1..10000

EXAMPLE

a(1) = 1 because 1 mod 2 = 1 where 2 = smallest prime >= 1.

MAPLE

a:= n-> add(n mod ithprime(i), i=1..numtheory[pi](nextprime(n-1))):

seq(a(n), n=1..60); # Alois P. Heinz, Nov 25 2010

CROSSREFS

Cf. A007918, A099726.