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A112055
a(n) = A112054(n)/6.
3
2, 3, 5, 7, 8, 12, 13, 15, 17, 18, 20, 22, 23, 27, 28, 30, 32, 33, 35, 37, 38, 40, 42, 43, 47, 48, 50, 52, 53, 55, 57, 58, 62, 63, 65, 67, 68, 70, 72, 73, 75, 77, 78, 82, 83, 85, 87, 88, 90, 92, 93, 97, 98, 100, 102, 103, 107, 108, 110, 112, 113, 117, 118, 120, 122
OFFSET
1,1
MATHEMATICA
a112046[n_]:=Block[{i=1}, While[JacobiSymbol[i, 2n + 1]==1, i++]; i]; Select[Range[1000], a112046[2#] - a112046[2# - 1] != 0 &]/6 (* Indranil Ghosh, May 25 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(2*n) - a112046(2*n - 1)
print([n//6 for n in range(1, 201) if a(n)!=0]) # Indranil Ghosh, May 25 2017
CROSSREFS
Cf. A112054, A112082 (complement), A112085 (first differences).
Sequence in context: A352204 A224858 A090704 * A291485 A228898 A352695
KEYWORD
nonn
AUTHOR
Antti Karttunen, Aug 27 2005
STATUS
approved