A318837 Restricted growth sequence transform of A318836.

1, 2, 2, 2, 2, 3, 2, 3, 3, 4, 2, 5, 2, 6, 7, 8, 2, 9, 2, 7, 10, 11, 2, 12, 4, 13, 9, 10, 2, 14, 2, 15, 16, 17, 18, 19, 2, 20, 21, 22, 2, 23, 2, 16, 24, 25, 2, 26, 6, 27, 28, 21, 2, 29, 30, 31, 32, 33, 2, 34, 2, 35, 36, 37, 38, 39, 2, 28, 40, 41, 2, 42, 2, 43, 44, 32, 45, 46, 2, 47, 29, 48, 2, 49, 50, 51, 52, 53, 2, 54, 55, 40, 56, 57, 58, 59, 2, 60, 61, 44, 2

Offset

1,2

Links

Antti Karttunen, Table of n, a(n) for n = 1..65537

Formula

For all i, j: a(i) = a(j) => A062790(i) = A062790(j).

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; };
A007431(n) = sumdiv(n, d, moebius(n/d)*eulerphi(d));
A318836(n) = { my(m=1); fordiv(n, d, if((d<n)&&(A007431(d)!=0), m *= prime(A007431(d)))); (m); }; \\
v318837 = rgs_transform(vector(up_to, n, A318836(n)));
A318837(n) = v318837[n];

Crossrefs

Cf. A007431, A062790, A318836.

Sequence in context: A029383 A341737 A351033 * A070098 A029233 A147981

Adjacent sequences: A318834 A318835 A318836 * A318838 A318839 A318840

Keyword

nonn

Author

Antti Karttunen, Sep 05 2018

Status

approved