A141791 Primes of the form c(n)-n, where c(n)=n-th composite.

3, 5, 5, 5, 7, 7, 7, 11, 13, 13, 13, 17, 17, 17, 17, 17, 19, 19, 19, 19, 19, 23, 23, 23, 29, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 37, 37, 37, 37, 37, 41, 41, 41, 41, 41, 43, 43, 43, 43, 43, 43, 43, 43, 43, 47, 47, 47, 47, 47, 47, 47, 47, 47, 47, 47, 53, 59, 59, 59, 59, 59

Offset: 1

Author

Juri-Stepan Gerasimov, Sep 13 2008, Feb 15 2009

Keywords

• nonn

Comments

c(n)=A002808(n).

Entries may be repeated and are shown in order of increasing generator n.

Examples

			n=1: c(1)-1=4-1=3=a(1).
n=3: c(3)-3=8-3=5=a(2).
n=4: c(4)-4=9-4=5=a(3).
n=5: c(5)-5=10-5=5=a(4).
n=7: c(7)-7=14-7=7=a(5).
		

Links

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

Crossrefs

Cf. A000040, A051697, A002808.

Programs

Mathematica

Module[{cmps=Select[Range[300],CompositeQ]},Select[#[[1]]-#[[2]]&/@ Thread[ {cmps,Range[Length[cmps]]}],PrimeQ]] (* Harvey P. Dale, Jan 15 2020 *)

Extensions

Corrected and extended by R. J. Mathar, Sep 26 2008