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A326501
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a(n) = Sum_{k=0..n} (-k)^k.
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2
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1, 0, 4, -23, 233, -2892, 43764, -779779, 15997437, -371423052, 9628576948, -275683093663, 8640417354593, -294234689237660, 10817772136320356, -427076118244539019, 18019667955465012597, -809220593930871751580, 38537187481365665823844
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OFFSET
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0,3
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LINKS
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FORMULA
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MAPLE
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a:= proc(n) option remember; `if`(n<0, 0, (-n)^n+a(n-1)) end:
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MATHEMATICA
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RecurrenceTable[{a[0] == 1, a[n] == a[n-1] + (-n)^n}, a, {n, 0, 23}] (* Jean-François Alcover, Nov 27 2020 *)
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PROG
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(PARI) {a(n) = sum(k=0, n, (-k)^k)}
(Python)
from itertools import accumulate, count, islice
def A326501_gen(): # generator of terms
yield from accumulate((-k)**k for k in count(0))
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CROSSREFS
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KEYWORD
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sign,easy
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AUTHOR
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STATUS
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approved
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