A289626 Restricted growth sequence transform of A289625, related to the structure of multiplicative group of integers modulo n.

1, 1, 2, 2, 3, 2, 4, 5, 4, 3, 6, 5, 7, 4, 8, 8, 9, 4, 10, 8, 11, 6, 12, 13, 14, 7, 10, 11, 15, 8, 16, 17, 18, 9, 19, 11, 20, 10, 19, 21, 22, 11, 23, 18, 19, 12, 24, 21, 23, 14, 25, 19, 26, 10, 27, 28, 29, 15, 30, 21, 31, 16, 32, 25, 33, 18, 34, 25, 35, 19, 36, 28, 37, 20, 27, 29, 38, 19, 39, 40, 41, 22, 42, 28, 43, 23, 44, 45, 46, 19, 47, 35, 38, 24, 48, 49

Offset: 1

Author

Antti Karttunen, Jul 18 2017

Keywords

• nonn

Links

• Antti Karttunen, Table of n, a(n) for n = 1..16384

Crossrefs

Cf. A289625, A101296.

Cf. A000010, A002322, A034380, A046072, A289624 (some of the matching sequences).

Programs

PARI

rgs_transform(invec) = { my(occurrences = Map(), outvec = vector(length(invec)), u=1); for(i=1, length(invec), if(mapisdefined(occurrences,invec[i]), my(pp = mapget(occurrences, invec[i])); outvec[i] = outvec[pp] , mapput(occurrences,invec[i],i); outvec[i] = u; u++ )); outvec; };
write_to_bfile(start_offset,vec,bfilename) = { for(n=1, length(vec), write(bfilename, (n+start_offset)-1, " ", vec[n])); }
A289625(n) = { my(m=1,p=2,v=znstar(n)[2]); for(i=1,length(v),m *= p^v[i]; p = nextprime(p+1)); (m); };
write_to_bfile(1,rgs_transform(vector(16384,n,A289625(n))),"b289626_upto16384.txt");