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A242307
Squares-greedy summable numbers.
3
5, 10, 13, 14, 17, 20, 21, 25, 26, 29, 30, 34, 35, 37, 40, 41, 45, 46, 49, 50, 53, 54, 58, 59, 62, 63, 65, 68, 69, 73, 74, 77, 78, 80, 81, 82, 85, 86, 90, 91, 94, 95, 97, 98, 101, 104, 105, 109, 110, 113, 114, 116, 117, 120, 121, 122, 125, 126, 130, 131, 134
OFFSET
1,1
COMMENTS
Greedy sums and summability are defined at A242305.
LINKS
EXAMPLE
a(1) = 5 = 4 + 1; a(2) = 9 + 1
a(3) = 13 = 9 + 4; a(4) = 14 = 9 + 4 + 1.
MATHEMATICA
z = 200; s = Table[n^2, {n, 1, z}]; s1 = Table[n, {n, 1, z}]; t = Table[{s1[[n]], #, Total[#] == s1[[n]]} &[DeleteCases[-Differences[FoldList[If[#1 - #2 >= 0, #1 - #2, #1] &, s1[[n]],
Reverse[Select[s, # < s1[[n]] &]]]], 0]], {n, z}]
r[n_] := s1[[n]] - Total[t[[n]][[2]]];
tr = Table[r[n], {n, 2, z}] (* A242305 *)
c = Table[Length[t[[n]][[2]]], {n, 2, z}] (* A242306 *)
f = 1 + Flatten[Position[tr, 0]] (* A242307 *) (* Peter J. C. Moses, May 06 2014 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, May 11 2014
STATUS
approved