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A236347
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Manhattan distances between n and 2*n in a left-aligned triangle with next M natural numbers in row M: 1, 2 3, 4 5 6, 7 8 9 10, etc.
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1
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1, 1, 2, 2, 3, 3, 4, 3, 2, 3, 2, 3, 4, 5, 6, 5, 6, 7, 5, 4, 3, 9, 4, 3, 4, 5, 6, 10, 5, 6, 7, 8, 9, 8, 7, 6, 10, 11, 12, 6, 5, 4, 5, 6, 7, 4, 5, 6, 7, 8, 9, 10, 12, 11, 10, 10, 11, 12, 13, 14, 9, 8, 7, 6, 5, 6, 17, 18, 6, 5, 6, 7, 8, 9, 10, 11, 16, 15, 9, 10, 11, 12
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OFFSET
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1,3
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LINKS
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EXAMPLE
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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
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PROG
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(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))+', ',
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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