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 A048442 Take the first n numbers written in base 11, concatenate them, then convert from base 11 to base 10. 16

%I

%S 1,13,146,1610,17715,194871,2143588,23579476,259374245,2853116705,

%T 345227121316,41772481679248,5054470283189021,611590904265871555,

%U 74002499416170458170,8954302429356625438586,1083470593952151678068923,131099941868210353046339701

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

%H Vincenzo Librandi, <a href="/A048442/b048442.txt">Table of n, a(n) for n = 1..200</a>

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

%t 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 *)

%t f[n_]:= FromDigits[Flatten@IntegerDigits[Range@n, 11], 11]; Array[f, 20] (* _Vincenzo Librandi_, Dec 30 2012 *)

%o (PARI) { cuo=0;

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

%o while(casi != 0,

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

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

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

%o \\ _Douglas Latimer_, May 09 2012

%o (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

%Y Cf. A014881.

%Y Concatenation of first n numbers in other bases: 2: A047778, 3: A048435, 4: A048436, 5: A048437, 6: A048438, 7: A048439, 8: A048440, 9: A048441, 10: A007908, 11: this sequence, 12: A048443, 13: A048444, 14: A048445, 15: A048446, 16: A048447.

%K nonn,base,easy

%O 1,2

%A _Patrick De Geest_, May 15 1999

%E 1 more term from _Douglas Latimer_, May 10 2012

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Last modified February 19 22:04 EST 2020. Contains 332060 sequences. (Running on oeis4.)