A072764 - OEIS

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A072764

Tabular N X N -> N bijection induced by Lisp/Scheme function 'cons' combining the two planar binary trees/general trees/parenthesizations encoded by A014486(X) and A014486(Y).

1, 3, 2, 7, 6, 4, 8, 16, 14, 5, 17, 19, 42, 15, 9, 18, 44, 51, 43, 37, 10, 20, 47, 126, 52, 121, 38, 11, 21, 53, 135, 127, 149, 122, 39, 12, 22, 56, 154, 136, 385, 150, 123, 40, 13, 45, 60, 163, 155, 413, 386, 151, 124, 41, 23, 46, 128, 177, 164, 475, 414, 387, 152 (list; table; graph; refs; listen; history; internal format)

	OFFSET	`1,2`
	LINKS	`Index entries for the sequences induced by list functions of Lisp` `Index entries for sequences that are permutations of the natural numbers` `A. Karttunen, Gatomorphisms (with the complete Scheme source)`
	PROG	`(Scheme functions showing the general idea:)` `(define (A072764bi x y) (A080300 (parenthesization->binexp (cons (binexp->parenthesization (A014486 x)) (binexp->parenthesization (A014486 y))))))` `(define (A072764 n) (cond ((zero? n) n) (else (A072764bi (A025581 (-1+ n)) (A002262 (-1+ n))))))`
	CROSSREFS	`Inverse permutation: A072765. a(n) = A069770(A072766(n)). Also transpose of A072766, i.e. a(n) = A072766(A038722(n)). The upper triangular region: A072773. Projection functions are A072771 ('car') & A072772 ('cdr'). The sizes of the corresponding Catalan structures: A072768. The first row: A057548, the first column: A072795, diagonal: A083938. Cf. also A080300, A025581, A002262.` `Sequence in context: A006068 A154436 A201566 * A130328 A083569 A071574` `Adjacent sequences: A072761 A072762 A072763 * A072765 A072766 A072767`
	KEYWORD	`nonn,tabl`
	AUTHOR	`Antti Karttunen (HisFirstname.HisSurname(AT)iki.fi) Jun 12 2002`

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Last modified February 14 22:03 EST 2012. Contains 205668 sequences.