A160793 Natural numbers and the sum of first n primes interleaved.

1, 2, 2, 5, 3, 10, 4, 17, 5, 28, 6, 41, 7, 58, 8, 77, 9, 100, 10, 129, 11, 160, 12, 197, 13, 238, 14, 281, 15, 328, 16, 381, 17, 440, 18, 501, 19, 568, 20, 639, 21, 712, 22, 791, 23, 874, 24, 963, 25, 1060, 26, 1161, 27, 1264, 28, 1371, 29, 1480

Offset: 1

Author

Omar E. Pol, May 29 2009

Keywords

• easy
• nonn

Comments

Also first differences of A160792: length of edges of a square spiral related to prime numbers A000040 whose vertices are the numbers A160792.

A000027 and A007504 interleaved. - Omar E. Pol, Oct 31 2011

Links

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

Crossrefs

Cf. A000040, A160790, A160791, A160792.

Programs

Mathematica

Module[{nn=30,sp},sp=Accumulate[Prime[Range[nn]]];Riffle[Range[nn],sp]] (* Harvey P. Dale, May 22 2018 *)

Formula

a(2n-1) = n, a(2n) = A007504(n). - Omar E. Pol, Oct 31 2011

Extensions

More terms from Sean A. Irvine, Oct 31 2011

New definition from Omar E. Pol, Oct 31 2011