A022451 a(1) = 3; a(n+1) = a(n)-th composite.

3, 8, 15, 25, 38, 55, 77, 105, 140, 183, 235, 298, 372, 462, 566, 692, 838, 1007, 1205, 1432, 1698, 2002, 2352, 2755, 3210, 3731, 4322, 4990, 5747, 6601, 7562, 8638, 9854, 11211, 12731, 14422, 16315, 18425, 20765, 23372, 26258, 29460, 32998, 36912, 41229

Offset: 1

Author

Clark Kimberling

Keywords

• nonn

References

• C. Kimberling, Fractal sequences and interspersions, Ars Combinatoria, vol. 45 p 157 1997.

Links

• Chai Wah Wu, Table of n, a(n) for n = 1..900
• C. Kimberling, Interspersions

Crossrefs

Cf. A006508, A022450, A025010, A025011.

Programs

Mathematica

g[ n_Integer ] := (k = n + PrimePi[ n ] + 1; While[ k - PrimePi[ k ] - 1, k++ ]; k); NestList[ g, 3, 45 ]
With[{comps=Complement[Range[80000],Prime[Range[PrimePi[80000]]]]}, NestList[comps[[#+1]]&,3,50]] (* Harvey P. Dale, Mar 17 2012 *)