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A122401
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Subsequence of A074139 omitting values derived from partitions with a part of size 1.
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2
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1, 3, 4, 5, 9, 6, 12, 7, 15, 16, 27, 8, 18, 20, 36, 9, 21, 24, 25, 45, 48, 81, 10, 24, 28, 30, 54, 60, 64, 108, 11, 27, 32, 35, 63, 36, 72, 75, 80, 135, 144, 243, 12, 30, 36, 40, 72, 42, 84, 90, 96, 162, 100, 180, 192, 324, 13, 33, 40, 45, 81, 48, 96, 49, 105, 112, 189, 108, 120, 216, 125, 225, 240, 405, 256, 432, 729, 14, 36, 44, 50, 90, 54
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graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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0,2
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COMMENTS
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When viewed as a table, row sums are given by sequence A079274.
Corresponds to members of A036035 which are also powerful numbers (A001694).
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LINKS
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EXAMPLE
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The two cyclic partitions of five are 5 and 3+2 yielding (5+1)=6 and (3+1)*(2+1) = 4*3 = 12
The array begins
1
(empty)
3
4
5 9
6 12
7 15 16 27
8 18 20 36
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MAPLE
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local e, a, L;
L := [] ;
for e in ListTools[Reverse](partition(n)) do
if member(1, e) then
;
else
a := 1;
for p in e do
a := a*(p+1) ;
end do:
L := [op(L), a] ;
end if;
end do:
L ;
end proc:
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CROSSREFS
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KEYWORD
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easy,nonn,tabf
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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