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A317627
a(n) = A317253 - floor(8*n/3).
2
2, 3, 1, 1, 3, 1, 2, 1, -1, 1, 3, 1, 2, 3, 1, 1, 1, -1, 2, 1, -1, 1, 3, 1, 2, 3, 1, 1, 3, 1, 2, 1, -1, 1, 1, -1, 2, 3, 1, 1, 1, -1, 2, 1, -1, 1, 3, 1, 2, 3, 1, 1, 3, 1, 2, 1, -1, 1, 3, 1, 2, 3, 1, 1, 1, -1, 2, 1, -1, 1, 1, -1, 2, 3, 1, 1, 3, 1, 2
OFFSET
1,1
FORMULA
a(3*n+1) = 2 - (n mod 2) for n >= 0, a(6*n+2) = 3 - 2*(n mod 2) and a(6*n+5) = a(3*n+2) for n >= 0, a(6*n+3) = 1 - 2*(n mod 2) and a(6*n+6) = a(3*n+3) for n >= 0.
a(3*n+1) = A000034(n+1) for n >= 0.
a(3*n+2) = A089607(n) for n > 1.
a(3*n+2) = 2*A014577(n-1)+1 for n > 0.
a(3*n+3) = A034947(n) = 2*A014577(n-1)-1 for n > 0.
PROG
(Python)
n, f, i, p, q, base = 1, 1, 0, 0, 1, 3
while i < 100000:
i, p, q = i+1, p*base, q*base
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 == 1:
n = n+1
print(n, a-1-(8*n//3))
CROSSREFS
KEYWORD
sign
AUTHOR
A.H.M. Smeets, Aug 02 2018
STATUS
approved