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A341330
a(n) = Sum_{k=1..n} (-k)^(k+1).
0
1, -7, 74, -950, 14675, -265261, 5499540, -128718188, 3358066213, -96641933787, 3041786442934, -103951418936138, 3833424966763151, -151734670591049073, 6416673685121841552, -288731231494230984304, 13774353220573494006705, -694460992134764182350927
OFFSET
1,2
MATHEMATICA
Accumulate[(-#)^(#+1)&/@Range[17]]
PROG
(PARI) a(n) = sum(i=1, n, (-i)^(i+1));
(Python)
sum = 0
for i in range(1, 20):
sum += (-i)**(i+1)
print(sum, end = ", ")
CROSSREFS
Sequence in context: A000901 A295245 A365844 * A266305 A098118 A097821
KEYWORD
sign
AUTHOR
John H. Chakkour, Feb 09 2021
STATUS
approved