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A145827
Numbers n such that A145768(n) is a square.
7
0, 1, 7, 9, 14, 15, 16, 24, 33, 63, 89, 193, 240, 255, 271, 430, 448, 528, 575, 729, 742, 783, 903, 1297, 1776, 2409, 2623, 3494, 4079, 4159, 5439, 8278, 13631, 13737, 16128, 41825, 53007, 64344, 95985, 99015, 100607, 138238, 147734, 198976, 256177, 262079, 262335, 278847
OFFSET
1,3
PROG
(PARI) an=0; for(i=1, 10^5, an=bitxor(an, i^2); issquare(an)&print1(i", "))
(Python)
import math
x = 0
for i in range(1<<20):
x ^= i*i
t = int(math.sqrt(x))
if x == t*t:
print(str(i), end=', ')
# Alex Ratushnyak, Mar 27 2013
CROSSREFS
A145828 = A145768 intersect A000290 = { A145768(a(n)) }.
Sequence in context: A365986 A063189 A004472 * A116025 A344011 A320325
KEYWORD
easy,base,nonn
AUTHOR
M. F. Hasler, Oct 20 2008
EXTENSIONS
More terms from Alex Ratushnyak, Mar 27 2013
STATUS
approved