%I #39 Oct 19 2020 11:31:41
%S 2,1,1,3,9,7,21,63,157,471,5,15,45,135,405,1215,3645,10935,32805,
%T 98415,295245,885735,2657205,4409119,2741597,8224791,16285765,
%U 15302863,45908589,137725767,77632981,232898943,161825917,485477751,1456433253,3027122479,1565174669
%N a(n) is the least positive number k such that 3^n+k has n prime factors counted with multiplicity.
%H David A. Corneth, <a href="/A337219/b337219.txt">Table of n, a(n) for n = 1..56</a>
%t a[n_] := Module[{k = 1}, While[PrimeOmega[3^n + k] != n, k++]; k]; Array[a, 20] (* _Amiram Eldar_, Sep 18 2020 *)
%o (PARI) a(n) = for(k=1, oo, if(bigomega(3^n+k)==n,return(k))); \\ _Daniel Suteu_, Oct 17 2020
%Y Cf. A078843.
%K nonn
%O 1,1
%A _Zak Seidov_, Sep 14 2020
%E a(27)-a(37) from _Daniel Suteu_, Sep 14 2020
%E Definition edited by _Zak Seidov_, Oct 17 2020
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