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A317335
a(n) = A317332(n) - 8*n.
6
1, 1, -2, 1, 1, -2, -2, 1, 1, 1, -2, -2, 1, -2, -2, 1, 1, 1, -2, 1, 1, -2, -2, -2, 1, 1, -2, -2, 1, -2, -2, 1, 1, 1, -2, 1, 1, -2, -2, 1, 1, 1, -2, -2, 1, -2, -2, -2, 1, 1, -2, 1, 1, -2, -2, -2, 1, 1, -2, -2, 1, -2, -2
OFFSET
1,3
LINKS
FORMULA
a(4*n-3) = 1, a(4*n-1) = -2, a(2*n) = a(n) for n > 0.
abs(a(n)+1) = A014710(n-1).
abs(a(n)) = A014709(n-1).
PROG
(Python)
n, f, i, p, q = 1, 1, 0, 0, 1
while i < 1000000:
....i, p, q = i+1, p*10, q*10
....if i == f:
........p, n = p+1, n+1
........f = f*n
n, a, j = 0, 0, 0
while p%q > 0:
....a, f, p, q = a+1, p//q, q, p%q
....if f == 8:
........n = n+1
........print(n, a-1-8*n)
CROSSREFS
KEYWORD
sign
AUTHOR
A.H.M. Smeets, Jul 26 2018
STATUS
approved