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A102487
Numbers in base-12 representation that can be written with decimal digits.
10
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 84, 85, 86
OFFSET
1,3
COMMENTS
Numbers that are only in this sequence or only in A039274 but not in both are n= 131, 142, 275, 286, 419, 430 etc: see A039558. [From R. J. Mathar, Aug 30 2008]
LINKS
Eric Weisstein's World of Mathematics, Duodecimal
Wikipedia, Duodecimal
MATHEMATICA
fQ[n_] := Last@ Union@ IntegerDigits[n, 12] < 10; Select[ Range[0, 86], fQ] (* Robert G. Wilson v, Apr 17 2012 *)
PROG
(PARI) {for(testn=0, 87,
lgt=1;
for(i=1, 1000, if(12^i > testn, lgt=i; break()));
atst=testn; pasr=1;
for(j=1, lgt, lasd=atst%12;
if(lasd<10, atst=(atst-lasd)/12, pasr=0; break()));
if(pasr==1, print1(testn, ", ")))}
\\ Douglas Latimer, Apr 17 2012
(Haskell)
import Data.List (unfoldr)
a102487 n = a102487_list !! (n-1)
a102487_list = filter (all (< 10) . unfoldr (\x ->
if x == 0 then Nothing else Just $ swap $ divMod x 12)) [0..]
-- Reinhard Zumkeller, Apr 18 2011
(Python)
A102487_list = [int(str(x), 12) for x in range(10**6)] # Chai Wah Wu, Apr 09 2016
CROSSREFS
Complement of A102488; A102489, A102491, A102493.
Cf. A033048 (subsequence).
Sequence in context: A056167 A050759 A039274 * A343951 A102234 A174908
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Jan 12 2005
STATUS
approved