OFFSET
1,3
EXAMPLE
Triangle in which we find distances begins:
_1
_2 3
_4 5 6
_7 8 9 10
11 12 13 14 15
16 17 18 19 20 21
22 23 24 25 26 27 28
29 30 31 32 33 34 35 36
37 38 39 40 41 42 43 44 45
PROG
(Python)
import math
def getXY(n):
y = int(math.sqrt(n*2))
if n<=y*(y+1)/2: y-=1
x = n - y*(y+1)/2
return x, y
for n in range(1, 88):
ox, oy = getXY(n)
nx, ny = getXY(2*n)
print str(abs(nx-ox)+abs(ny-oy))+', ',
CROSSREFS
KEYWORD
nonn
AUTHOR
Alex Ratushnyak, Jan 23 2014
STATUS
approved