OFFSET

1,2

COMMENTS

LINKS

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

PROG

(PARI)

up_to = 100000;

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; };

A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));

Aux374040(n) = { my(d=A003415(n)); [d, gcd(n, d), valuation(n, 2), valuation(n, 3)]; };

v374040 = rgs_transform(vector(up_to, n, Aux374040(n)));

A374040(n) = v374040[n];

CROSSREFS

KEYWORD

nonn

AUTHOR

Antti Karttunen, Jul 01 2024

STATUS

approved