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%I #31 Jun 04 2021 04:40:51
%S 2,3,5,6,9,10,12,13,14,17,18,20,21,22,23,25,26,27,29,30,31,32,34,35,
%T 36,37,38,39,40,41,44,46,47,48,49,50,51,52,53,55,56,57,58,59,60,61,62,
%U 63,64,65,66,67,68,70,72,73,74,75,76,77,78,80,81,82,83,84,85,86,88,89,90,91,93,94
%N Positions of primes among the powers of primes (A000961).
%H Reinhard Zumkeller, <a href="/A024620/b024620.txt">Table of n, a(n) for n = 1..10000</a>
%F A025474(a(n)) = 1. - _Reinhard Zumkeller_, May 01 2015
%F a(n) = A001222(A056604(n)) + 1. - _Eric Desbiaux_, Dec 02 2018
%F From _Ridouane Oudra_, Oct 18 2020: (Start)
%F a(n) = A027883(n) + 1;
%F a(n) = A025528(A000040(n)) + 1;
%F a(n) = A065515(A000040(n)). (End)
%t a[n_] := PrimeOmega[LCM @@ Range@Prime@n] + 1; Array[a, 100] (* _Amiram Eldar_, Dec 02 2018 *)
%o (PARI) lista(nn) = my(powpr = select((i->((omega(i)==1) || (i==1))), [1..nn])); for (i = 1, #powpr, if (isprime(powpr[i]), print1(i, ", ")); ); \\ _Michel Marcus_, Jun 03 2021
%o (Haskell)
%o a024620 n = a024620_list !! (n-1)
%o a024620_list = filter ((== 1) . a025474) [1..]
%o -- _Reinhard Zumkeller_, May 01 2015
%Y Complement of A024621.
%Y Cf. A001222 (bigomega), A025474, A056604, A027883.
%Y Cf. A025528, A065515, A000040.
%K nonn
%O 1,1
%A _Clark Kimberling_
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