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A121266
Triangle read by rows: row n (n>= 10) gives n-10 successive bases used in computing A121263(n) followed by A121263(n) itself.
6
10, 11, 11, 12, 13, 13, 13, 15, 16, 16, 14, 17, 19, 20, 20, 15, 19, 22, 24, 25, 25, 16, 21, 25, 28, 30, 31, 31, 17, 23, 28, 32, 35, 37, 38, 38, 18, 25, 31, 36, 40, 43, 45, 46, 46, 19, 27, 34, 40, 45, 49, 52, 54, 55, 55, 20, 29, 37, 44, 50, 55, 59, 62, 64, 65, 65
OFFSET
10,1
COMMENTS
Left-hand entry of row n is n, right-hand entry is A121263(n).
A "dungeon" of numbers.
REFERENCES
David Applegate, Marc LeBrun and N. J. A. Sloane, Descending Dungeons and Iterated Base-Changing, in "The Mathematics of Preference, Choice and Order: Essays in Honor of Peter Fishburn", edited by Steven Brams, William V. Gehrlein and Fred S. Roberts, Springer, 2009, pp. 393-402.
LINKS
David Applegate, Marc LeBrun and N. J. A. Sloane, Descending Dungeons and Iterated Base-Changing, arXiv:math/0611293 [math.NT], 2006-2007.
David Applegate, Marc LeBrun, N. J. A. Sloane, Descending Dungeons, Problem 11286, Amer. Math. Monthly, 116 (2009) 466-467.
EXAMPLE
Triangle begins:
10
11 11
12 13 13
13 15 16 16
14 17 19 20 20
15 19 22 24 25 25
16 21 25 28 30 31 31
17 23 28 32 35 37 38 38
18 25 31 36 40 43 45 46 46
19 27 34 40 45 49 52 54 55 55
20 29 37 44 50 55 59 62 64 65 65
MAPLE
M:=45; a:=list(10..M): a[10]:=10: a[10]; for n from 11 to M do b:=n; lprint(b); for i from n-1 by -1 to 11 do t1:=convert(i, base, 10); b:=add(t1[j]*b^(j-1), j=1..nops(t1)): lprint(b); od: a[n]:=b; lprint(a[n]); od:
CROSSREFS
Cf. A121263.
Sequence in context: A087381 A136400 A334027 * A045988 A008947 A108787
KEYWORD
nonn,tabl,base,look
AUTHOR
N. J. A. Sloane, Aug 23 2006
STATUS
approved