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A112050
Length of the longest prefix of 1's in the Jacobi-vector {J(2n+1,1),J(2n+1,2),...,J(2n+1,2n)}.
2
1, 1, 2, 2, 1, 1, 2, 2, 1, 1, 4, 4, 1, 1, 2, 2, 1, 1, 2, 2, 1, 1, 4, 6, 1, 1, 2, 2, 1, 1, 2, 2, 1, 1, 6, 4, 1, 1, 2, 2, 1, 1, 2, 2, 1, 1, 4, 4, 1, 1, 2, 2, 1, 1, 2, 2, 1, 1, 6, 10, 1, 1, 2, 2, 1, 1, 2, 2, 1, 1, 4, 4, 1, 1, 2, 2, 1, 1, 2, 2, 1, 1, 4, 12, 1, 1, 2, 2, 1, 1, 2, 2, 1, 1, 6, 4, 1, 1, 2, 2, 1, 1
OFFSET
1,3
FORMULA
a(n) = A112046(n) - 1.
MATHEMATICA
a112046[n_]:=Block[{i=1}, While[JacobiSymbol[i, 2n + 1]==1, i++]; i]; Table[a112046[n] - 1, {n, 102}] (* Indranil Ghosh, May 24 2017 *)
PROG
(Python)
from sympy import jacobi_symbol as J
def a112046(n):
i=1
while True:
if J(i, 2*n + 1)!=1: return i
else: i+=1
def a(n): return a112046(n) - 1
print([a(n) for n in range(1, 103)]) # Indranil Ghosh, May 24 2017
CROSSREFS
Cf. A112046.
Sequence in context: A112049 A055230 A290262 * A283156 A298231 A320473
KEYWORD
nonn
AUTHOR
Antti Karttunen, Aug 27 2005
EXTENSIONS
Name clarified by Joerg Arndt, May 24 2017
STATUS
approved