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Least common multiple of the digit reversals of the first n natural numbers.
1

%I #20 Sep 25 2024 19:48:19

%S 1,2,6,12,60,60,420,840,2520,2520,27720,27720,859320,35232120,

%T 598946040,36535708440,2594035299240,23346317693160,303502130011080,

%U 303502130011080,303502130011080,303502130011080,1214008520044320,1214008520044320,1214008520044320

%N Least common multiple of the digit reversals of the first n natural numbers.

%C a(1) to a(12) are the same as in A003418.

%H Harvey P. Dale, <a href="/A109935/b109935.txt">Table of n, a(n) for n = 1..1000</a>

%p rev:=proc(n) local nn, nnn: nn:=convert(n,base,10): add(nn[nops(nn)+1-j]*10^(j-1),j=1..nops(nn)) end: a:=n->lcm(seq(rev(j),j=1..n)): seq(a(n),n=1..27); # _Emeric Deutsch_, Aug 03 2005

%t Table[LCM@@IntegerReverse/@Range[n],{n,30}] (* _Harvey P. Dale_, Sep 25 2024 *)

%o (PARI) r(n) = fromdigits(Vecrev(digits(n))); \\ A004086

%o a(n) = lcm(vector(n, i, r(i))); \\ _Michel Marcus_, Aug 15 2019

%Y Cf. A003418, A004086.

%K base,nonn

%O 1,2

%A _Amarnath Murthy_, Jul 19 2005

%E Corrected and extended by _Emeric Deutsch_ and _Erich Friedman_, Aug 03 2005