A320113 Filter sequence for counting the residue classes mod 12 of divisors of n.

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 5, 17, 7, 18, 19, 20, 11, 21, 22, 23, 24, 25, 5, 26, 7, 27, 28, 10, 29, 30, 13, 14, 31, 32, 5, 33, 7, 34, 35, 20, 11, 36, 37, 38, 15, 39, 5, 40, 29, 41, 19, 10, 11, 42, 13, 14, 43, 44, 45, 46, 7, 18, 28, 47, 11, 48, 13, 23, 49, 25, 29, 50, 7, 51, 52, 10, 11, 53, 45, 14, 15, 54, 5, 55, 56, 34, 19, 20, 29, 57, 13, 58, 59, 60, 5

Offset

1,2

Comments

Restricted growth sequence transform of A320112.

For all i, j:

a(i) = a(j) => A320115(i) = A320115(j).

a(i) = a(j) => A320117(i) = A320117(j).

Links

Antti Karttunen, Table of n, a(n) for n = 1..100000

Prog

(PARI)
up_to = 100000;
A320112(n) = { my(m=1); fordiv(n, d, if(d>1, m *= prime(1+(d%12)))); (m); };
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; };
v320113 = rgs_transform(vector(up_to, n, A320112(n)));
A320113(n) = v320113[n];

Crossrefs

Cf. A320109, A320112, A320115, A320117.

Sequence in context: A309083 A375245 A106618 * A080684 A159062 A301274

Adjacent sequences: A320110 A320111 A320112 * A320114 A320115 A320116

Keyword

nonn

Author

Antti Karttunen, Oct 06 2018

Status

approved