A222089 Where records occur in A222084.

1, 2, 4, 8, 16, 24, 48, 96, 192, 384, 480, 768, 960, 1920, 3840, 5760, 7680, 11520, 19440, 23040, 26880, 46080, 53760, 80640, 107520, 161280, 215040, 322560, 612360, 645120, 967680, 1224720, 1290240, 1935360, 2580480, 3870720, 5160960, 6451200, 7096320

Offset: 1

Author

Paolo P. Lava, Feb 13 2013

Keywords

• nonn

Comments

Like A002182 but using tau#(n), as defined in A222084, instead of tau(n).

Examples

			tau#(8)=4 and not until n=16 this value is overtaken: tau#(16)=5.
		

Crossrefs

Cf. A000005, A000961, A001358, A003418, A005179, A024619, A034444, A077610, A222084, A222085.

Programs

Maple

with(numtheory);
A222089:=proc(q)
local a,b,c,j,n,t;
t:=0;
for n from 1 to q do
a:=ifactors(n)[2]; b:=nops(a); c:=0;
for j from 1 to b do if a[j][1]^a[j][2]>c then c:=a[j][1]^a[j][2]; fi; od;
a:=op(sort([op(divisors(n))])); b:=nops(divisors(n));
for j from 1 to b do if a[j]=c then break; fi; od;
if j>t then t:=j; print(n); fi;
od; end:
A222089(10000000000);

Mathematica

f[n_]:= Module[{d = Divisors[n], k = 1}, While [LCM@@d[[1;;k]] != n, k++]; k]; fm=0; s={}; Do[f1=f[n]; If[f1>fm, fm=f1; AppendTo[s,n]], {n, 1, 10000}]; s (* Amiram Eldar, Jan 19 2019 *)

PARI

f(n) = {my(d = divisors(n), k = 1); while (lcm(vector(k, j, d[j])) != n, k++); k; } \\ A222084
lista(nn) = {my(m=0, nm); for( n=1, nn, if ((nm=f(n)) > m, print1(n, ", "); m = nm););} \\ Michel Marcus, Jan 19 2019

Extensions

a(2) inserted and a(32)-a(39) added by Amiram Eldar, Jan 19 2019