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A263259
a(n) = number of integers k <= n for which A155043(k) = A155043(n).
6
1, 1, 2, 1, 2, 1, 3, 1, 2, 3, 4, 2, 5, 1, 3, 2, 3, 1, 4, 1, 4, 2, 5, 1, 2, 3, 4, 1, 5, 1, 6, 1, 3, 2, 4, 1, 2, 1, 2, 2, 3, 1, 4, 1, 2, 2, 3, 2, 4, 3, 4, 1, 5, 1, 6, 2, 7, 1, 3, 1, 8, 1, 2, 2, 3, 1, 3, 1, 3, 2, 4, 1, 4, 1, 3, 2, 4, 1, 5, 1, 6, 3, 4, 2, 4, 3, 4, 3, 5, 2, 6, 3, 4, 4, 5, 5, 5, 2, 4, 3, 6, 2, 5, 3, 7, 3, 5, 4, 8, 3, 6, 4, 7, 2, 7, 3, 8, 4, 4, 2, 7
OFFSET
0,3
COMMENTS
a(n) = one-based index of n in row A155043(n) of table A263265.
LINKS
FORMULA
Other identities. For all n >= 0:
a(A261089(n)) = 1.
a(A262503(n)) = A262507(n).
A263265(A155043(n), a(n)) = n.
PROG
(Scheme, with memoizing definec-macro)
(definec (A263259 n) (cond ((zero? n) 1) ((= 1 (- (A263089 n) (A263089 (- n 1)))) 1) (else (let ((d (A155043 n))) (let loop ((k (- n 1))) (if (= (A155043 k) d) (+ 1 (A263259 k)) (loop (- k 1))))))))
KEYWORD
nonn
AUTHOR
Antti Karttunen, Nov 24 2015
STATUS
approved