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Triangle read by rows: row n contains numbers with sum of digits = n, and not greater than the n-th repunit (cf. A007953 and A002275).
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%I #7 Oct 08 2019 11:13:55

%S 0,1,2,11,3,12,21,30,102,111,4,13,22,31,40,103,112,121,130,202,211,

%T 220,301,310,400,1003,1012,1021,1030,1102,1111,5,14,23,32,41,50,104,

%U 113,122,131,140,203,212,221,230,302,311,320,401,410,500,1004,1013,1022

%N Triangle read by rows: row n contains numbers with sum of digits = n, and not greater than the n-th repunit (cf. A007953 and A002275).

%C Number of terms in row n = A242622(n);

%C T(n,1) = A051885(n);

%C T(n,A242622(n)) = A002275(n);

%C for n > 0: number of repdigit terms in row n = A242627(n).

%H Reinhard Zumkeller, <a href="/A242614/b242614.txt">Rows n = 0..8 of table, flattened</a>

%e The triangle begins:

%e . 0: 0

%e . 1: 1

%e . 2: 2,11

%e . 3: 3,12,21,30,102,111

%e . 4: 4,13,22,31,40,103,112,121,130,202, . . . ,1021,1030,1102,1111

%e . 5: 5,14,23,32,41,50,104,113,122,131, . . . ,11021,11030,11102,11111 .

%t Join[{0},Flatten[Table[Select[Range[FromDigits[PadRight[{},n,1]]], Total[ IntegerDigits[ #]] == n&],{n,5}]]] (* _Harvey P. Dale_, Oct 08 2019 *)

%o (Haskell)

%o a242614 n k = a242614_row n !! (k-1)

%o a242614_row n = filter ((== n) . a007953) [n .. a002275 n]

%o a242614_tabf = map a242614_row [0..]

%Y Cf. A007953 (sum of digits), A002275 (repunits).

%Y Cf. A011557, A052216, A052217, A052218, A052219, A052220, A052221, A052222, A052223, A052224, A166311, A235151, A143164, A235225, A235226, A235227, A166370, A235228, A166459, A235229.

%K nonn,tabf,base

%O 0,3

%A _Reinhard Zumkeller_, Jul 16 2014