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A295876 Restricted growth sequence transform of A023900, Product_{p|n} (1-p). 4

%I

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

%T 18,19,2,20,21,22,5,23,24,22,7,25,9,26,15,11,27,28,5,6,7,29,14,30,5,

%U 31,10,32,33,34,18,35,36,14,2,37,38,39,21,40,41,42,5,43,32,11,24,44,41,45,7,3,31,46,9,47,48,49,15,50,18,51,27,44,52,51,5,53,10

%N Restricted growth sequence transform of A023900, Product_{p|n} (1-p).

%C For all i, j:

%C a(i) = a(j) => A092248(i) = A092248(j).

%C a(i) = a(j) => A295877(i) = A295877(j).

%H Antti Karttunen, <a href="/A295876/b295876.txt">Table of n, a(n) for n = 1..65536</a>

%o (PARI)

%o allocatemem(2^30);

%o up_to = 65536;

%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 A023900(n) = sumdivmult(n, d, d*moebius(d)); \\ This function from _Charles R Greathouse IV_, Sep 09 2014

%o write_to_bfile(1,rgs_transform(vector(up_to,n,A023900(n))),"b295876.txt");

%Y Cf. A023900, A092248, A295877.

%K nonn

%O 1,2

%A _Antti Karttunen_, Nov 29 2017

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Last modified August 10 12:39 EDT 2020. Contains 336379 sequences. (Running on oeis4.)