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A205565 Number of ways of writing n = u + v with u <= v, and u,v having in ternary representation no 3. 2
1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 2, 4, 2, 1, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 2, 4, 2, 1, 2, 1, 2, 4, 2, 4, 8, 4, 2, 4, 2, 1, 2, 1, 2, 4, 2, 1, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 2, 4, 2, 1, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 2, 4 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,5

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 0..10000

EXAMPLE

a(30) = #{0+30, 3+27} = 2;

a(31) = #{0+31, 1+30, 3+28, 4+27} = 4;

a(32) = #{1+31, 4+28} = 2;

a(33) = #{3+30} = 1;

a(34) = #{3+31, 4+30} = 2;

a(35) = #{4+31} = 1;

a(36) = #{0+36, 9+27} = 2;

a(37) = #{0+37, 1+36, 9+28, 10+27} = 4;

a(38) = #{1+37, 10+28} = 2;

a(39) = #{0+39, 3+36, 9+30, 12+27} = 4;

a(40) = #{0+40, 1+39, 3+37, 4+36, 9+31, 10+30, 12+28, 13+27} = 8.

PROG

(Haskell)

a205565 n = sum $ map (a039966 . (n -)) $

                  takeWhile (<= n `div` 2) a005836_list

CROSSREFS

Cf. A039966, A005836, A120880.

Sequence in context: A184170 A025919 A095684 * A064531 A274468 A211993

Adjacent sequences:  A205562 A205563 A205564 * A205566 A205567 A205568

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Jan 28 2012

STATUS

approved

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Last modified July 24 23:25 EDT 2021. Contains 346273 sequences. (Running on oeis4.)