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%I #22 Mar 15 2015 01:47:06
%S 1,3,9,27,121,403,1209,3627,14921,52803,162409,491227,2273721,7225203,
%T 22083609,106254827,319172521,957521603,2953364809,12940502427,
%U 42902311321,132707334003,402122410009,2010408030027,6031224090121,18093712270403,54285137211209
%N Powers of 3 in base 60, concatenating the decimal values of the sexagesimal digits.
%C Each sexagesimal digit appears as a pair of decimal digits as on a digital clock. Any leading zeros are truncated. Thus decimal 81 appears as "121" and not "0121".
%H Michael De Vlieger, <a href="/A254334/b254334.txt">Table of n, a(n) for n = 0..1200</a>
%F a(n) = A055643(A000244(n)). - _Michel Marcus_, Mar 02 2015
%e a(6) = 1209, since 3^6 = 729 = 12 * 60^1 + 9, thus 12:09 in clock-like notation, which becomes 1209 when restricted to numeric characters.
%t f[n_] := FromDigits@ StringJoin[If[# < 10, StringJoin["0", ToString[#]], ToString[#]] & /@ IntegerDigits[3^n, 60]]; Table[f@ i, {i, 0, 26}] (* _Michael De Vlieger_, Jan 28 2015 *)
%o (PARI) a(n) = subst(Pol(digits(3^n, 60)), x, 100); \\ _Michel Marcus_, Feb 22 2015
%o (Python)
%o def digits(n,b=10): # list of digits of n in base b
%o ....x, y = n, []
%o ....while x >= b:
%o ........x, r = divmod(x,b)
%o ........y.append(r)
%o ....y.append(x)
%o ....return list(reversed(y))
%o A254334_list = [int(''.join([format(x,'02d') for x in digits(3**i, 60)])) for i in range(10**2)]
%o # _Chai Wah Wu_, Mar 14 2015
%Y Cf. A000244 (Powers of 3), A055643 (Babylonian numbers).
%Y Cf. Sexagesimal representations: A250073 (Powers of 2), A254335 (Powers of 5), A254336 (Powers of 10).
%K nonn,base
%O 0,2
%A _Michael De Vlieger_, Jan 28 2015
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