A336320 Lexicographically earliest infinite sequence such that a(i) = a(j) => A324058(i) = A324058(j) for all i, j >= 0.

1, 1, 2, 1, 2, 3, 1, 1, 2, 2, 3, 4, 1, 5, 4, 1, 2, 6, 4, 7, 4, 8, 7, 3, 5, 5, 2, 1, 4, 8, 1, 5, 2, 4, 3, 9, 4, 10, 2, 11, 4, 12, 8, 8, 2, 13, 14, 4, 1, 5, 7, 1, 7, 3, 1, 5, 4, 4, 8, 6, 1, 5, 2, 1, 2, 2, 4, 3, 4, 10, 7, 6, 15, 6, 8, 16, 7, 8, 6, 2, 4, 12, 8, 17, 6, 18, 3, 14

Offset

0,3

Comments

Restricted growth sequence transform of A324058.

Links

Antti Karttunen, Table of n, a(n) for n = 0..65537

Prog

(PARI)
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; };
A005940(n) = { my(p=2, t=1); n--; until(!n\=2, if((n%2), (t*=p), p=nextprime(p+1))); t }; \\ From A005940
A324121(n) = gcd(sigma(n), n*numdiv(n));
A324058(n) = A324121(A005940(1+n));
v336320 = rgs_transform(vector(1+up_to, n, A324058(n-1)));
A336320(n) = v336320[1+n];

Crossrefs

Cf. A005940, A324121, A324058.

Cf. also A286622.

Sequence in context: A272210 A273132 A294859 * A145782 A131797 A145727

Adjacent sequences: A336317 A336318 A336319 * A336321 A336322 A336323

Keyword

nonn

Author

Antti Karttunen, Jul 19 2020

Status

approved