cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A235591 Numbers which on division by their digital root give quotient which is divisible by its digital root.

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%I A235591 #6 Jan 14 2014 11:43:47
%S A235591 1,2,3,4,5,6,7,8,9,10,12,18,19,20,21,24,27,28,30,36,37,38,40,42,45,46,
%T A235591 50,54,55,56,57,60,63,64,70,72,73,74,76,80,81,82,84,90,91,92,95,100,
%U A235591 108,109,110,111,112,114,118,120,127,128,133,136,138,140,145,146,148,152,154,162,163,164,165,168,171,172
%N A235591 Numbers which on division by their digital root give quotient which is divisible by its digital root.
%e A235591  108 is a term as on division by its digital root i.e. 9, gives 12, which is again divisible by its digital root i.e. 3.
%t A235591 dr[n_] := 1 + Mod[n-1, 9]; Select[Range@172, IntegerQ[q = #/dr@#] && Mod[q, dr@q] == 0 &] (* _Giovanni Resta_, Jan 14 2014 *)
%K A235591 nonn,base,easy
%O A235591 1,2
%A A235591 _Mihir Mathur_, Jan 12 2014