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A147778 Positive integers of the form u*v*(u^2 - v^2) where u, v are coprime integers. 3
6, 24, 30, 60, 84, 120, 180, 210, 240, 330, 336, 504, 546, 630, 720, 840, 924, 990, 1224, 1320, 1386, 1560, 1710, 1716, 2016, 2184, 2310, 2340, 2520, 2574, 2730, 3036, 3360, 3570, 3696, 3900, 3960, 4080, 4290, 4620, 4896, 4914, 5016, 5280, 5544, 5610, 5814 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Terms with even u or v form A024365. Squarefree terms form A147779.

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

MAPLE

N:= 10^5:

A:= {}:

for v from 1 to floor((N/2)^(1/3)) do

   for u from v+1 do

      if igcd(u, v) = 1 then

        t:= u*v*(u^2-v^2);

        if t > N then break fi;

        A:= A union {t};

      fi

    od

od:

A;

# if using Maple 11 or earlier, uncomment the next line

# sort(convert(A, list)); # Robert Israel, Apr 06 2015

CROSSREFS

Subsequence of: A003273, A009112, A073120.

Sequence in context: A332962 A132398 A073120 * A209452 A275302 A201596

Adjacent sequences:  A147775 A147776 A147777 * A147779 A147780 A147781

KEYWORD

nonn

AUTHOR

Max Alekseyev, Nov 12 2008

STATUS

approved

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Last modified June 21 04:10 EDT 2021. Contains 345354 sequences. (Running on oeis4.)