A163061 Sum of the first n primes plus the first n nonprimes.
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
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.
Links
- Harvey P. Dale, Table of n, a(n) for n = 1..1000
Programs
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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 *)
Extensions
Formula index corrected, 1119 replaced by 1159 - R. J. Mathar, Jul 27 2009