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%I #20 Aug 09 2016 15:25:25
%S 1,3,4,2,6,3,8,4,9,5,12,6,14,7,15,8,18,9,20,10,21,11,24,12,25,13,27,
%T 14,30,15,32,16,33,17,35,18,38,19,39,20,42,21,44,22,45,23,48,24,49,25,
%U 51,26,54,27,55,28,57,29,60,30,62,31,63,32,65,33,68,34,69,35,72,36,74,37
%N If n is prime, a(n) = n+1; if n is even, a(n) = n/2; otherwise a(n) = n.
%H Harvey P. Dale, <a href="/A082928/b082928.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = A026741(n) + A010051(n), for n>2; with a(1) = 1, a(2) = 3. - _Wesley Ivan Hurt_, Oct 04 2014
%t Join[{1, 3}, Table[Numerator[n/2] + Boole[PrimeQ[n]], {n, 3, 50}]] (* _Wesley Ivan Hurt_, Oct 04 2014 *)
%t Table[Which[PrimeQ[n],n+1,EvenQ[n],n/2,True,n],{n,80}] (* _Harvey P. Dale_, Aug 09 2016 *)
%o (PARI) a(n)={if(isprime(n),n+1,if(n%2,n,n/2))}
%Y Cf. A010051, A026741.
%K easy,nonn
%O 1,2
%A _Cino Hilliard_, May 26 2003
%E Edited by _Charles R Greathouse IV_, Oct 09 2009
%E Offset corrected by _Thomas Ordowski_, Oct 03 2014
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