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A105648
Smallest member of a set of Smith triples.
2
73615, 209065, 225951, 283745, 305455, 342879, 656743, 683670, 729066, 747948, 774858, 879221, 954590, 1185547, 1262722, 1353955, 1369374, 1495718, 1622495, 1666434, 1790480, 2197579, 2299772, 2428854, 2561678, 2576441, 2580367, 2636516, 2665480, 2707580, 2741816
OFFSET
1,1
COMMENTS
If there are 3 consecutive numbers which are Smith numbers, these can be called a Smith triple.
LINKS
S. S. Gupta, Smith Numbers.
EXAMPLE
a(1) = 73615 because 73615 is the smallest of 3 consecutive integers which are Smith numbers, i.e., the three consecutive numbers 73615, 73616, 73617 are all Smith numbers.
MATHEMATICA
digSum[n_] := Plus @@ IntegerDigits[n]; smithQ[n_] := CompositeQ[n] && Plus @@ (Last@#*digSum[First@#] & /@ FactorInteger[n]) == digSum[n]; sm = smithQ /@ Range[3]; seq = {}; Do[sm = Join[Rest[sm], {smithQ[k]}]; If[And @@ sm, AppendTo[seq, k - 2]], {k, 4, 10^6}]; seq (* Amiram Eldar, Aug 18 2020 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Shyam Sunder Gupta, May 03 2005
EXTENSIONS
More terms from Amiram Eldar, Aug 18 2020
STATUS
approved