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A291764 Restricted growth sequence transform of A291784, (psi(n) + phi(n))/2.

%I A291764 #5 Sep 10 2017 14:54:11
%S A291764 1,2,3,4,5,6,6,7,8,9,9,10,11,12,13,13,14,15,16,17,17,18,18,19,20,21,
%T A291764 21,22,23,24,25,26,27,28,29,30,31,32,24,33,34,35,36,37,38,39,39,40,41,
%U A291764 42,43,35,44,45,40,46,47,48,48,49,50,45,51,52,51,53,54,55,55,56,57,56,58,59,49,60,60,61,62,63,64,65,65,66,67,68,63,69,70,71,69,72,72
%N A291764 Restricted growth sequence transform of A291784, (psi(n) + phi(n))/2.
%H A291764 Antti Karttunen, <a href="/A291764/b291764.txt">Table of n, a(n) for n = 1..65537</a>
%o A291764 (PARI)
%o A291764 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 A291764 write_to_bfile(start_offset,vec,bfilename) = { for(n=1, length(vec), write(bfilename, (n+start_offset)-1, " ", vec[n])); }
%o A291764 A291784(n) = (eulerphi(n)+n*sumdivmult(n, d, issquarefree(d)/d))\2; \\ This function from _M. F. Hasler_
%o A291764 write_to_bfile(1,rgs_transform(vector(65537,n,A291784(n))),"b291764_upto65537.txt");
%Y A291764 Cf. A000010, A001615, A291784.
%K A291764 nonn
%O A291764 1,2
%A A291764 _Antti Karttunen_, Sep 10 2017