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A304105
Restricted growth sequence transform of A304104, a filter sequence related to how the divisors of n are expressed in Fibonacci number system.
7
1, 2, 2, 3, 2, 4, 5, 6, 7, 4, 5, 8, 2, 9, 4, 10, 11, 12, 11, 8, 6, 9, 13, 14, 15, 4, 16, 17, 5, 18, 11, 8, 19, 20, 9, 21, 13, 22, 4, 23, 11, 24, 25, 26, 27, 28, 5, 29, 30, 31, 32, 8, 33, 34, 6, 35, 36, 9, 11, 37, 25, 22, 12, 38, 39, 40, 33, 41, 16, 42, 25, 43, 11, 44, 45, 46, 47, 18, 11, 48, 49, 50, 51, 52, 53, 54, 19, 55, 2, 56, 9, 57, 22, 9, 58, 59, 13, 60
OFFSET
1,2
LINKS
FORMULA
For all i, j: a(i) = a(j) => b(i) = b(j), where b can be any of {A000005, A005086, A304096 or A300837} for example.
PROG
(PARI)
\\ Needs also code from A304101:
up_to = 65537;
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; };
write_to_bfile(start_offset, vec, bfilename) = { for(n=1, length(vec), write(bfilename, (n+start_offset)-1, " ", vec[n])); }
A304104(n) = { my(m=1); fordiv(n, d, if(d>1, m *= prime(A304101(d)-1))); (m); };
write_to_bfile(1, rgs_transform(vector(up_to, n, A304104(n))), "b304105.txt");
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, May 13 2018
STATUS
approved