login
Powers of 5 in base 60, concatenating the decimal values of the sexagesimal digits.
5

%I #13 Mar 12 2015 18:37:59

%S 1,5,25,205,1025,5205,42025,214205,1483025,9023205,45124025,346032205,

%T 1850165025,13411241205,75057010025,391445050205,3161345251025,

%U 16210847055205,121454355292025,648483937264205,3404031807133025,25020163036073205,141141223300374025,1105826524503082205,5545214234515415025

%N Powers of 5 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 125 appears as "205" and not "0205".

%H Michael De Vlieger, <a href="/A254335/b254335.txt">Table of n, a(n) for n = 0..1200</a>

%F a(n) = A055643(A000351(n)). - _Michel Marcus_, Mar 02 2015

%e a(4) = 1025, since 5^4 = 625 = 10 * 60^1 + 25, thus 10:25 in clock-like notation, which becomes 1025 when restricted to numeric characters.

%t f[n_] := FromDigits@ StringJoin[If[# < 10, StringJoin["0", ToString[#]],

%t ToString[#]] & /@ IntegerDigits[5^n, 60]]; Table[f@ i, {i, 0, 24}] (* _Michael De Vlieger_, Jan 28 2015 *)

%o (PARI) a(n) = subst(Pol(digits(5^n, 60)), x, 100); \\ _Michel Marcus_, Feb 22 2015

%Y Cf. A000351 (Powers of 5), A055643 (Babylonian numbers).

%Y Cf. Sexagesimal representations: A250073 (Powers of 2), A254334 (Powers of 3), A254336 (Powers of 10).

%K nonn,base

%O 0,2

%A _Michael De Vlieger_, Jan 28 2015