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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..102.

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

Adjacent sequences:  A112047 A112048 A112049 * A112051 A112052 A112053

KEYWORD

nonn

AUTHOR

Antti Karttunen, Aug 27 2005

EXTENSIONS

Name clarified by Joerg Arndt, May 24 2017

STATUS

approved

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Last modified June 22 14:15 EDT 2021. Contains 345380 sequences. (Running on oeis4.)