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A072039
Row of Zorach additive triangle in which n appears (or 0 in the unlikely event that it does not).
4
1, 2, 2, 3, 5, 3, 4, 6, 3, 7, 4, 5, 6, 8, 9, 11, 4, 7, 10, 12, 13, 14, 5, 8, 6, 4, 15, 17, 9, 16, 7, 19, 18, 10, 11, 12, 21, 20, 22, 5, 13, 8, 14, 23, 24, 26, 27, 6, 15, 35, 25, 30, 9, 28, 29, 7, 16, 17, 31, 33, 18, 32, 10, 34, 19, 5, 36, 40, 11, 20, 12, 37, 8, 39, 21, 22, 13, 38, 45, 43
OFFSET
1,2
FORMULA
If a(n) > 0: n = A035312(a(n)-1, A072038(n)-1).
EXAMPLE
a(8)=6 since 8 appears in the sixth row.
PROG
(Haskell) -- See link.
CROSSREFS
KEYWORD
nonn
AUTHOR
Henry Bottomley, Jun 07 2002
STATUS
approved