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A263257
a(n) = least number with distance n to the infinite trunk (A259934) of the tree defined by edge-relation A049820(child) = parent.
5
0, 1, 3, 5, 7, 19, 23, 27, 29, 31, 35, 37, 41, 43, 51, 53, 57, 59, 61, 65, 67, 71, 73, 77, 79, 223, 231, 233, 237, 239, 241, 249, 251, 263, 267, 269, 271, 277, 285, 291, 293, 299, 303, 315, 317, 321, 327, 331, 335, 337, 341, 347, 349, 357, 359, 369, 857, 859, 1077, 1081, 1087, 1095, 1097, 1101
OFFSET
0,3
COMMENTS
a(n) = least number k for which A263254(k) = n.
Also positions of records in A263254, thus the sequence is strictly increasing.
LINKS
PROG
(Scheme, three alternatives implementations)
(define A263257 (RECORD-POS 0 0 A263254)) ;; Uses Antti Karttunen's IntSeq-library
(define (A263257 n) (let loop ((k 0)) (if (= (A263254 k) n) k (loop (+ 1 k)))))
(define (A263257 n) (A263255bi n 1)) ;; A263255bi given in A263255.
CROSSREFS
First column of array A263255.
Sequence in context: A052333 A074106 A002261 * A261456 A154524 A184805
KEYWORD
nonn
AUTHOR
Antti Karttunen, Nov 07 2015
STATUS
approved