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%I #12 Aug 18 2020 04:22:53
%S 4463535,6356910,8188933,9425550,11148564,15966114,15966115,18542654,
%T 21673542,22821992,23767287,28605144,36615667,39227466,47096634,
%U 47395362,48072396,54054264,55464835,57484614,57756450,57761165,58418508,61843387,62577157,64572186,65484066
%N Smallest member of set of 4 consecutive numbers which are Smith numbers.
%H Amiram Eldar, <a href="/A105649/b105649.txt">Table of n, a(n) for n = 1..1000</a>
%H S. S. Gupta, <a href="http://www.shyamsundergupta.com/smith.htm">Smith Numbers</a>.
%e a(1) = 4463535 because 4463535 is the smallest member of a set of 4 consecutive numbers which are Smith numbers i.e. four consecutive numbers 4463535, 4463536, 4463537, 4463538 are all Smith numbers.
%t digSum[n_] := Plus @@ IntegerDigits[n]; smithQ[n_] := CompositeQ[n] && Plus @@ (Last @#* digSum[First@#] & /@ FactorInteger[n]) == digSum[n]; sm = smithQ /@ Range[4]; seq = {}; Do[sm = Join[Rest[sm], {smithQ[k]}]; If[And @@ sm, AppendTo[seq, k - 3]], {k, 5, 10^7}]; seq (* _Amiram Eldar_, Aug 18 2020 *)
%Y Cf. A006753, A050219, A059754, A105648, A105650.
%K nonn,base
%O 1,1
%A _Shyam Sunder Gupta_, May 03 2005
%E a(7) inserted and more terms added by _Amiram Eldar_, Aug 18 2020
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