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%I #22 Jan 14 2021 21:16:27
%S 8,87,875,8757,87571,875719,8757193,87571931,875719319,8757193191
%N The largest n-digit number whose first k digits are divisible by the k-th prime for k = 1..n.
%C There are 10 terms in the series; the 10-digit number 8757193191 is the largest number to satisfy the requirements.
%e There are four one-digit numbers divisible by the first prime (2) and the largest is 8, so a(1)=8.
%e For two-digit numbers, the second digit must make it divisible by 3, which gives 87 as the largest to satisfy the requirement, so a(2)=87.
%t a=Table[j, {j,2,8,2}]; r=2; t={}; While[!a == {}, n=Length[a]; nmax=Last[a]; k=1; b={}; While[!k>n, z0=a[[k]]; Do[z=10*z0+j; If[Mod[z, Prime[r]]==0, b=Append[b, z]], {j, 0, 9}]; k++]; AppendTo[t, nmax]; a=b; r++]; t
%Y Subsequence of A079206.
%Y Cf. A143867, A225614.
%K nonn,base,fini,full
%O 1,1
%A _Shyam Sunder Gupta_, Aug 04 2013
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