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A165955 n-th odd nonprime plus n-th even nonprime. 1
1, 13, 21, 29, 35, 39, 47, 51, 57, 65, 71, 75, 81, 85, 93, 97, 103, 111, 115, 121, 127, 131, 137, 141, 145, 151, 159, 167, 173, 177, 181, 185, 189, 193, 199, 205, 209, 217, 221, 225, 229, 237, 241, 247, 251, 257, 263, 267, 273, 277, 285, 289, 293, 297, 305, 313, 317, 321, 325 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..5000

FORMULA

a(n) = A014076(n) + A163300(n).

EXAMPLE

a(1) = 1+0 = 1. a(2) = 9+4 = 13. a(3) = 15+6 = 21.

MATHEMATICA

A014076 := Select[Range@500, ! PrimeQ@# && OddQ@# &]; A163300 := Drop[Range[0, 500, 2], {2}]; Table[(A163300[[n]] + A014076[[n]]), {n, 1, 50}] (* G. C. Greubel, Sep 17 2017 *)

Module[{nn=300, np, enp, onp, len}, np=Select[Range[0, nn], !PrimeQ[#]&]; enp= Select[ np, EvenQ]; onp=Select[np, OddQ]; len=Min[Length[enp], Length[ onp]]; Total/@Thread[{Take[enp, len], Take[onp, len]}]] (* Harvey P. Dale, Nov 28 2018 *)

CROSSREFS

Cf. A014076, A141468, A163300.

Sequence in context: A087683 A195375 A128819 * A331116 A050711 A282844

Adjacent sequences:  A165952 A165953 A165954 * A165956 A165957 A165958

KEYWORD

nonn

AUTHOR

Juri-Stepan Gerasimov, Oct 01 2009

EXTENSIONS

Entries checked by R. J. Mathar, Oct 10 2009

STATUS

approved

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Last modified September 29 14:39 EDT 2020. Contains 337432 sequences. (Running on oeis4.)