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editing
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<a href="/index/Ch#char_fns">Index entries for characteristic functions</a>
For n > 9: a(n) * a(n+1) = 0 and 0 <= a(n) + a(n+1) <= 1.
(Haskell)
a228710 n = fromEnum $ f (n `div` 10) (n `mod` 2) where
f x p = x == 0 || (x `mod` 2) /= p && f (x `div` 10) (1 - p)
nonn,changed,base
allocated for Reinhard ZumkellerCharacteristic function of numbers with alternating parities of their digits in decimal representation.
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1
0
Reinhard Zumkeller, <a href="/A228710/b228710.txt">Table of n, a(n) for n = 0..10000</a>
allocated
nonn
Reinhard Zumkeller, Aug 31 2013
approved
editing
allocated for Reinhard Zumkeller
allocated
approved