A120326 Cumulative sum of the remainders when dividing primes by 3.

2, 2, 4, 5, 7, 8, 10, 11, 13, 15, 16, 17, 19, 20, 22, 24, 26, 27, 28, 30, 31, 32, 34, 36, 37, 39, 40, 42, 43, 45, 46, 48, 50, 51, 53, 54, 55, 56, 58, 60, 62, 63, 65, 66, 68, 69, 70, 71, 73, 74, 76, 78, 79, 81, 83, 85, 87, 88, 89, 91, 92, 94, 95, 97, 98, 100, 101, 102, 104, 105

Offset

1,1

Comments

Partial sums of A039701. - Michel Marcus, Jan 21 2015

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Formula

a(n) = sum_{k=1..n} (prime(k) mod 3).

Mathematica

s=0; lst={}; Do[p=Prime[n]; m=Mod[p, 3]; a=(p-m)/3; AppendTo[lst, s+=m], {n, 3*4!}]; lst (* Vladimir Joseph Stephan Orlovsky, May 24 2009 *)
Accumulate[Mod[Prime[Range[80]], 3]] (* Harvey P. Dale, Sep 17 2016 *)

Crossrefs

Cf. A039701 (prime(n) mod 3).

Sequence in context: A053036 A308840 A067957 * A036406 A029007 A338202

Adjacent sequences: A120323 A120324 A120325 * A120327 A120328 A120329

Keyword

nonn

Author

Joost de Winter, Aug 27 2006

Status

approved