cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A163061 Sum of the first n primes plus the first n nonprimes.

Original entry on oeis.org

2, 6, 15, 28, 47, 69, 96, 127, 164, 208, 255, 310, 371, 435, 504, 581, 665, 752, 846, 945, 1048, 1159, 1275, 1398, 1530, 1667, 1808, 1954, 2103, 2258, 2429, 2605, 2788, 2975, 3173, 3374, 3582, 3797, 4018, 4246, 4481, 4719, 4968, 5221, 5480, 5742
Offset: 1

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Author

Juri-Stepan Gerasimov, Jul 21 2009

Keywords

Examples

			a(1)=2+0=2. a(2)=5+1=6. a(3)=10+5=15. a(4)=17+11=28. a(5)=28+19=47. a(6)=41+28=69. a(7)=58+38=96.
		

Crossrefs

Programs

  • Mathematica
    Module[{nn=80,np,len},np=Select[Range[0,nn],!PrimeQ[#]&];len=Length[np];Total/@ Thread[{Accumulate[np],Accumulate[Prime[Range[len]]]}]] (* Harvey P. Dale, Jun 14 2019 *)

Formula

a(n)=A007504(n)+A051349(n-1).

Extensions

Formula index corrected, 1119 replaced by 1159 - R. J. Mathar, Jul 27 2009