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A161537
a(n) = n-th composite + n.
2
5, 8, 11, 13, 15, 18, 21, 23, 25, 28, 31, 33, 35, 38, 40, 42, 44, 46, 49, 52, 54, 56, 58, 60, 63, 65, 67, 70, 73, 75, 77, 80, 82, 84, 86, 88, 91, 93, 95, 97, 99, 102, 105, 107, 109, 111, 113, 116, 118, 120, 123, 126, 128, 130, 132, 134, 137, 139, 141, 144, 146, 148, 150
OFFSET
1,1
COMMENTS
Complement of A171511. [Jaroslav Krizek, Dec 13 2009]
LINKS
FORMULA
a(n) = A002808(n) + n = A002808(n) + A000027(n). [Jaroslav Krizek, Dec 10 2009]
EXAMPLE
a(1) = composite(1)+1 = 4 +1 = 5 ; a(2) = composite(2)+2 = 6+2=8.
MAPLE
Comps:= remove(isprime, [$4..200]):
seq(Comps[i]+i, i=1..nops(Comps)); # Robert Israel, Mar 23 2020
MATHEMATICA
c=0; Do[If[CompositeQ[n], c=c+1; Print[c+n]], {n, 1, 87}] (* Metin Sariyar, Mar 23 2020 *)
Range@ Length # + # &@ Select[Range[4, 87], CompositeQ] (* Michael De Vlieger, Mar 23 2020 *)
PROG
(PARI) my(n=0); forcomposite(k=4, 86, print1(k+n++, ", ")) \\ Hugo Pfoertner, Mar 23 2020
CROSSREFS
Sequence in context: A246371 A274939 A173977 * A248634 A189724 A220143
KEYWORD
nonn
AUTHOR
Claudio Meller, Jun 13 2009
STATUS
approved