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A293217 Restricted growth sequence transform of A293216, where A293216(n) = Product_{d|n, d<n} A260443(d). 10

%I

%S 1,2,2,3,2,4,2,5,6,7,2,8,2,9,10,11,2,12,2,13,14,15,2,16,4,8,17,18,2,

%T 19,2,20,21,22,17,23,2,13,24,25,2,26,2,27,28,29,2,30,31,32,33,34,2,35,

%U 36,37,38,39,2,40,2,41,42,43,44,45,2,46,47,48,2,49,2,27,50,51,44,52,2,53,54,55,2,56,57,58,59,60,2,61,62,63,64,65,66,67,2,68,69

%N Restricted growth sequence transform of A293216, where A293216(n) = Product_{d|n, d<n} A260443(d).

%C For all i, j: a(i) = a(j) => A001065(i) = A001065(j).

%H Antti Karttunen, <a href="/A293217/b293217.txt">Table of n, a(n) for n = 1..16384</a>

%o (PARI)

%o rgs_transform(invec) = { my(om = Map(), outvec = vector(length(invec)), u=1); for(i=1, length(invec), if(mapisdefined(om,invec[i]), my(pp = mapget(om, invec[i])); outvec[i] = outvec[pp] , mapput(om,invec[i],i); outvec[i] = u; u++ )); outvec; };

%o write_to_bfile(start_offset,vec,bfilename) = { for(n=1, length(vec), write(bfilename, (n+start_offset)-1, " ", vec[n])); }

%o A003961(n) = my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); \\ This function from _Michel Marcus_

%o A260443(n) = if(n<2, n+1, if(n%2, A260443(n\2)*A260443(n\2+1), A003961(A260443(n\2))));

%o A293216(n) = { my(m=1); fordiv(n,d,if(d < n,m *= A260443(d))); m; };

%o write_to_bfile(1,rgs_transform(vector(16384,n,A293216(n))),"b293217.txt");

%Y Cf. A001065, A260443, A293216, A293215 (a variant).

%K nonn

%O 1,2

%A _Antti Karttunen_, Oct 03 2017

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Last modified August 8 19:29 EDT 2020. Contains 336298 sequences. (Running on oeis4.)