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A222089 Where records occur in A222084. 1
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

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

LINKS

Table of n, a(n) for n=1..39.

EXAMPLE

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

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 *)

PROG

(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

CROSSREFS

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

Sequence in context: A138278 A326078 A089827 * A182763 A272709 A119311

Adjacent sequences:  A222086 A222087 A222088 * A222090 A222091 A222092

KEYWORD

nonn

AUTHOR

Paolo P. Lava, Feb 13 2013

EXTENSIONS

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

STATUS

approved

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Last modified September 19 14:43 EDT 2019. Contains 327198 sequences. (Running on oeis4.)