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.

A106372 Smallest number m containing no zeros in base n representation but at least one zero in all base b representations with 1

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%I A106372 #12 Nov 05 2017 14:37:33
%S A106372 1,2,6,12,20,60,147,384,896,360,1540,2760,2304,11016,13860,6720,
%T A106372 123060,255024,658370,1422720,1425606,1179360,2920500,12252240,
%U A106372 9989280,24227280,242573760,68424048,990208128,410810400,602751600
%N A106372 Smallest number m containing no zeros in base n representation but at least one zero in all base b representations with 1<b<n.
%C A106372 A106370(a(n)) = n and A106370(m) <> n for m < a(n).
%C A106372 a(46) = 854710136280. a(45) and all further terms are at least 10^13.
%H A106372 Michael Gottlieb, <a href="/A106372/b106372.txt">Table of n, a(n) for n = 2..44</a> (terms 2..32 from Reinhard Zumkeller, terms 33..44 from Michael Gottlieb).
%H A106372 Michael Gottlieb, <a href="/A106372/a106372.cpp.txt">C++ program to compute values.</a>
%e A106372 a(10)=896, A106370(896)=10: 896[base-9]='1205',
%e A106372 896[octal]='1600', 896[base-7]='2420', 896[base-6]='4052',
%e A106372 896[base-5]='12041', 896[base-4]='32000', 896[ternary]='1020012',
%e A106372 896[binary]='1110000000'.
%o A106372 (Haskell)
%o A106372 import Data.List (elemIndex); import Data.Maybe (fromJust)
%o A106372 a106372 = (+ 1) . fromJust . (`elemIndex` a106370_list)
%o A106372 -- _Reinhard Zumkeller_, Apr 12 2015
%Y A106372 Cf. A106370, A119354.
%K A106372 nonn,base
%O A106372 2,2
%A A106372 _Reinhard Zumkeller_, May 01 2005
%E A106372 Generated a(33)-a(44) and a(46), with linked C++ program