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A353306
Numbers k such that 1 is in the transitive closure of the map x -> A353313(x) when starting iterating from x=k.
1
1, 3, 4, 9, 12, 27, 36, 81, 108, 193, 243, 324, 346, 436, 579, 729, 972, 1038, 1308, 1522, 1737, 1867, 2187, 2353, 2539, 2916, 3114, 3493, 3924, 4234, 4566, 5211, 5601, 5824, 6286, 6561, 7059, 7617, 8748, 9342, 9446, 9709, 10479, 10886, 11756, 11772, 12702, 13698, 13772, 14792, 14806, 15633, 15745, 16184, 16803, 17003
OFFSET
1,2
PROG
(PARI)
A353313(n) = { my(r=(n%3)); if(!r, n/3, ((5*((n-r)/3)) + r + 3)); };
A353305(n) = { my(visited = Map(), m=0); for(j=1, oo, n = A353313(n); if(!m, m=n, m=min(m, n)); if(mapisdefined(visited, n), return(m), mapput(visited, n, j))); };
isA353306(n) = (1==A353305(n));
CROSSREFS
Positions of ones in A353305.
Subsequences: A000244, A003946, A211221.
Sequence in context: A002513 A034418 A034421 * A211221 A376684 A029448
KEYWORD
nonn
AUTHOR
Antti Karttunen, Apr 13 2022
STATUS
approved