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%I #8 Oct 18 2017 00:56:12
%S 1,2,2,2,2,6,2,12,6,6,2,36,2,4,18,12,2,30,2,360,12,10,2,540,6,60,30,
%T 360,2,900,2,120,30,10,12,2700,2,4,180,360,2,540,2,360,450,6,2,5400,4,
%U 120,30,360,2,210,30,5040,12,14,2,1701000,2,84,180,2520,180,1260,2,840,18,12600,2,94500,2,140,180,840,20,18900,2,756000,210,210,2,23814000,30
%N a(n) = Product_{d|n, d<n} A019565(A289813(d)); a product obtained from the 1-digits present in ternary expansions of proper divisors of n.
%H Antti Karttunen, <a href="/A293221/b293221.txt">Table of n, a(n) for n = 1..6561</a>
%F a(n) = Product_{d|n, d<n} A019565(A289813(d)).
%F For all n >= 0, a(3^n) = A002110(n).
%o (PARI)
%o A019565(n) = {my(j,v); factorback(Mat(vector(if(n, #n=vecextract(binary(n), "-1..1")), j, [prime(j), n[j]])~))}; \\ This function from _M. F. Hasler_
%o A289813(n) = { my (d=digits(n, 3)); fromdigits(vector(#d, i, if (d[i]==1, 1, 0)), 2); } \\ From _Remy Sigrist_
%o A293221(n) = { my(m=1); fordiv(n,d,if(d < n,m *= A019565(A289813(d)))); m; };
%Y Cf. A019565, A289813, A293214, A293222, A293223 (restricted growth sequence transform), A293226.
%Y Cf. also A290091.
%K nonn,base
%O 1,2
%A _Antti Karttunen_, Oct 03 2017
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