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A270308 Numbers which are less than the number of their ordered factorizations. 1
72, 96, 120, 144, 192, 216, 240, 288, 336, 360, 384, 432, 480, 504, 540, 576, 600, 648, 672, 720, 768, 840, 864, 960, 1008, 1080, 1152, 1200, 1260, 1296, 1344, 1440, 1512, 1536, 1584, 1620, 1680, 1728, 1800, 1872, 1920, 1944, 2016, 2112, 2160, 2240, 2304, 2400 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Also numbers which are less than the number of their perfect factorizations or gozinta chains.

LINKS

Paolo P. Lava, Table of n, a(n) for n = 1..100

FORMULA

Solution of the inequation n < A002033(n-1) = A074206(n).

EXAMPLE

The ordered partitions of 72 are 76, of 96 are 112, of 120 are 132, etc.

MAPLE

P:=proc(q) local a, j, k, m; a:= array(1..q); for k from 1 to q do a[k]:=0 od; a[1]:=1;

for j from 2 to q do for m from 1 to j-1 do if j mod m=0 then a[j]:= a[j]+a[m]; fi; od;

if j<a[j] then print(j); fi; od; end: P(10^5);

CROSSREFS

Cf. A002033, A074206, A163272.

Sequence in context: A063923 A030025 A245213 * A271329 A307867 A099943

Adjacent sequences:  A270305 A270306 A270307 * A270309 A270310 A270311

KEYWORD

nonn,easy

AUTHOR

Paolo P. Lava, Mar 15 2016

STATUS

approved

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Last modified August 20 06:04 EDT 2019. Contains 326139 sequences. (Running on oeis4.)