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A221643
Numbers k such that k^2 XOR (k+1)^2 is a square, where XOR is the bitwise XOR operator.
7
0, 3, 4, 23, 24, 43, 44, 76, 111, 112, 115, 139, 164, 180, 183, 248, 264, 323, 327, 348, 411, 479, 480, 499, 611, 699, 747, 787, 943, 976, 1072, 1103, 1111, 1176, 1268, 1388, 1447, 1576, 1684, 1851, 1983, 1984, 2008, 2243, 2692, 3271, 3383, 3452, 3464, 3532, 3679, 3804, 3867
OFFSET
1,2
PROG
(Python)
import math
for i in range(1<<16):
s = (i*i) ^ ((i+1)*(i+1))
t = int(math.sqrt(s))
if s == t*t:
print(str(i), end=', ')
CROSSREFS
Sequence in context: A316192 A122660 A163744 * A042595 A002351 A042035
KEYWORD
nonn,base
AUTHOR
Alex Ratushnyak, Mar 27 2013
STATUS
approved