A014420 - OEIS

A014420

Minimal number of Catalan numbers that sum to n.

0, 1, 1, 2, 2, 1, 2, 2, 3, 3, 2, 3, 3, 4, 1, 2, 2, 3, 3, 2, 3, 3, 4, 4, 3, 4, 4, 5, 2, 3, 3, 4, 4, 3, 4, 4, 5, 5, 4, 5, 5, 6, 1, 2, 2, 3, 3, 2, 3, 3, 4, 4, 3, 4, 4, 5, 2, 3, 3, 4, 4, 3, 4, 4, 5, 5, 4, 5, 5, 6, 3, 4, 4, 5, 5, 4, 5, 5, 6, 6, 5, 6, 6, 7, 2, 3, 3, 4, 4, 3, 4, 4, 5, 5, 4, 5, 5, 6, 3

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OFFSET

0,4

LINKS

Olivier Gérard (first 1001 terms) & Antti Karttunen, Table of n, a(n) for n = 0..16796

FORMULA

a(0) = 0, a(n) = 1 + a(n-A081290(n)). - Antti Karttunen, Jul 02 2014

PROG

(Scheme, with memoization macro definec from Antti Karttunen's IntSeq-library)

(definec (A014420 n) (if (zero? n) n (+ 1 (A014420 (- n (A081290 n))))))

;; Other version, requiring A014418raw given in A014418:

(define (A014420 n) (apply + (A014418raw n)))