A048442 - OEIS

A048442

Take the first n numbers written in base 11, concatenate them, then convert from base 11 to base 10.

1, 13, 146, 1610, 17715, 194871, 2143588, 23579476, 259374245, 2853116705, 345227121316, 41772481679248, 5054470283189021, 611590904265871555, 74002499416170458170, 8954302429356625438586, 1083470593952151678068923, 131099941868210353046339701

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OFFSET

1,2

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..200

EXAMPLE

a(11) = (1)(2)(3)(4)(5)(6)(7)(8)(9)(A)(10) = 123456789A10_11 = 345227121316.

MATHEMATICA

If[STARTPOINT==1, n={}, n=Flatten[IntegerDigits[Range[STARTPOINT-1], 11]]]; Table[AppendTo[n, IntegerDigits[w, 11]]; n=Flatten[n]; FromDigits[n, 11], {w, STARTPOINT, ENDPOINT}] (* Dylan Hamilton, Aug 11 2010 *)

f[n_]:= FromDigits[Flatten@IntegerDigits[Range@n, 11], 11]; Array[f, 20] (* Vincenzo Librandi, Dec 30 2012 *)

PROG

(PARI) { cuo=0;

for(ixp=1, 18, casi = ixp; cvst=0;

while(casi != 0,

cvd = casi%11; cvst=100*cvst + cvd + 1; casi = (casi - cvd) / 11 );

while(cvst !=0, ptch = cvst%100;

cuo=cuo*11+ptch-1; cvst = (cvst - ptch) / 100 ); print1(cuo, ", "))}

\\ Douglas Latimer, May 09 2012

(Magma) [n eq 1 select 1 else Self(n-1) * 11^(1+Ilog(11, n)) + n: n in [1..20]]; // Vincenzo Librandi, Dec 30 2012

CROSSREFS

Cf. A014881.