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A227365
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a(n) = 0 + 1*2 + 3*4*5 + 6*7*8*9 + ... + ...*n.
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5
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0, 1, 2, 5, 14, 62, 68, 104, 398, 3086, 3096, 3196, 4406, 20246, 243326, 243341, 243566, 247406, 316766, 1638686, 28150526, 28150547, 28150988, 28161152, 28405550, 34526126, 193916126, 4503821726, 4503821754, 4503822538, 4503846086, 4504576886, 4527986846, 5301270686
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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0,3
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LINKS
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EXAMPLE
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a(4) = 0 + 1*2 + 3*4 = 14.
a(5) = 0 + 1*2 + 3*4*5 = 62.
a(6) = 0 + 1*2 + 3*4*5 + 6 = 68.
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PROG
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(Python)
for n in range(55):
sum = i = 0
k = 1
while i<=n:
product = 1
for x in range(k):
product *= i
i += 1
if i>n: break
sum += product
k += 1
print(str(sum), end=', ')
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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