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A293892 Restricted growth sequence transform of A083722.

%I A293892 #8 Nov 02 2017 15:37:03
%S A293892 1,1,1,2,1,3,1,4,5,6,1,7,1,8,9,10,1,11,1,12,13,14,1,15,16,17,15,18,1,
%T A293892 19,1,20,21,22,23,24,1,25,26,27,1,28,1,29,30,31,1,32,33,34,35,36,1,37,
%U A293892 38,39,40,41,1,42,1,43,44,45,46,47,1,48,49,50,1,51,1,52,53,54,55,56,1,57,58,59,1,60,61,62,63,64,1,65,66,67,68,69,70,71,1,72,73
%N A293892 Restricted growth sequence transform of A083722.
%C A293892 a(n) = 1 iff n is prime or n is 1.
%H A293892 Antti Karttunen, <a href="/A293892/b293892.txt">Table of n, a(n) for n = 1..65536</a>
%o A293892 (PARI)
%o A293892 allocatemem(2^30);
%o A293892 up_to = 65536;
%o A293892 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 A293892 write_to_bfile(start_offset,vec,bfilename) = { for(n=1, length(vec), write(bfilename, (n+start_offset)-1, " ", vec[n])); }
%o A293892 A083722(n) = { if(n==1, return (1)); my(gpf = vecmax(factor(n)[, 1])); my(pp = 1); forprime(p=gpf+1, n, pp *= p; ); pp; } \\ This function from _Michel Marcus_, Jun 26 2016
%o A293892 write_to_bfile(1,rgs_transform(vector(up_to,n,A083722(n))),"b293892.txt");
%Y A293892 Cf. A083722, A293893, A293894.
%K A293892 nonn
%O A293892 1,4
%A A293892 _Antti Karttunen_, Nov 02 2017