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%I #13 Nov 09 2015 16:08:13
%S 0,1,3,5,7,19,23,27,29,31,35,37,41,43,51,53,57,59,61,65,67,71,73,77,
%T 79,223,231,233,237,239,241,249,251,263,267,269,271,277,285,291,293,
%U 299,303,315,317,321,327,331,335,337,341,347,349,357,359,369,857,859,1077,1081,1087,1095,1097,1101
%N a(n) = least number with distance n to the infinite trunk (A259934) of the tree defined by edge-relation A049820(child) = parent.
%C a(n) = least number k for which A263254(k) = n.
%C Also positions of records in A263254, thus the sequence is strictly increasing.
%H Antti Karttunen, <a href="/A263257/b263257.txt">Table of n, a(n) for n = 0..1835</a>
%o (Scheme, three alternatives implementations)
%o (define A263257 (RECORD-POS 0 0 A263254)) ;; Uses _Antti Karttunen_'s IntSeq-library
%o (define (A263257 n) (let loop ((k 0)) (if (= (A263254 k) n) k (loop (+ 1 k)))))
%o (define (A263257 n) (A263255bi n 1)) ;; A263255bi given in A263255.
%Y Cf. A049820, A259934, A263254, A263258.
%Y First column of array A263255.
%K nonn
%O 0,3
%A _Antti Karttunen_, Nov 07 2015