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A277816
a(n) = the least k > n for which A264977(k) = A264977(n), or 0 if no such k exists.
7
0, 5, 10, 39, 20, 13, 78, 11, 40, 21, 26, 19, 156, 29, 22, 27, 80, 25, 42, 35, 52, 45, 38, 43, 312, 37, 58, 51, 44, 41, 54, 59, 160, 57, 50, 67, 84, 53, 70, 75, 104, 61, 90, 79, 76, 93, 86, 55, 624, 101, 74, 99, 116, 77, 102, 71, 88, 69, 82, 115, 108, 85, 118, 123, 320, 121, 114, 131, 100, 117, 134, 91, 168, 89, 106, 147, 140, 109, 150, 83, 208, 105
OFFSET
0,2
LINKS
FORMULA
For all n >= 0, A277815(a(n)) = n.
PROG
(Scheme)
(define (A277816 n) (if (zero? n) n (let ((v (A264977 n))) (let loop ((k (+ 1 n))) (if (= v (A264977 k)) k (loop (+ 1 k)))))))
CROSSREFS
Cf. A277815 (a left inverse).
Cf. A277701, A277712, A277713, A277715 (iterates of this sequence starting from 1, 2, 3 and 9 respectively).
Sequence in context: A270276 A271604 A365690 * A359021 A355327 A279764
KEYWORD
nonn
AUTHOR
Antti Karttunen, Nov 06 2016
STATUS
approved