OFFSET
1,1
COMMENTS
LINKS
Reinhard Zumkeller, Table of n, a(n) for n = 1..10000
MAPLE
# A075321p implemented in A075321
A075323 := proc(n)
if type(n, 'odd') then
op(1, A075321p((n+1)/2)) ;
else
op(2, A075321p(n/2)) ;
end if;
end proc:
seq(A075323(n), n=1..60) ; # R. J. Mathar, Nov 26 2014
MATHEMATICA
A075321p[n_] := A075321p[n] = Module[{prevlist, i, p, q}, If[n == 1, Return[{3, 5}], prevlist = Array[A075321p, n - 1] // Flatten]; For[i = 2, True, i++, p = Prime[i]; If[FreeQ[prevlist, p], q = p + 2*n; If[PrimeQ[q] && FreeQ[prevlist, q], Return[{p, q}]]]]];
A075323[n_] := If[OddQ[n], A075321p[(n+1)/2][[1]], A075321p[n/2][[2]]];
PROG
(Haskell)
import Data.List ((\\))
a075323 n = a075323_list !! (n-1)
a075323_list = f 1 [] $ tail a000040_list where
f k ys qs = g qs where
g (p:ps) | a010051' pk == 0 || pk `elem` ys = g ps
| otherwise = p : pk : f (k + 1) (p:pk:ys) (qs \\ [p, pk])
where pk = p + 2 * k
-- Reinhard Zumkeller, Nov 29 2014
CROSSREFS
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Sep 14 2002
EXTENSIONS
Corrected by R. J. Mathar, Nov 26 2014
STATUS
approved