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Triangle read by rows in which the n-th row contains n multiples of n with digit sum n.
7

%I #24 Nov 26 2019 09:05:31

%S 1,2,20,3,12,21,4,40,112,220,5,50,140,230,320,6,24,42,60,114,132,7,70,

%T 133,322,511,700,1015,8,80,152,224,440,512,800,1016,9,18,27,36,45,54,

%U 63,72,81,190,280,370,460,550,640,730,820,910,1090,209,308,407,506,605,704,803,902,2090,3080,4070

%N Triangle read by rows in which the n-th row contains n multiples of n with digit sum n.

%H Alois P. Heinz, <a href="/A082259/b082259.txt">Rows n = 1..100, flattened</a>

%e Triangle begins:

%e 1

%e 2, 20;

%e 3, 12, 21;

%e 4, 40, 112, 220;

%e 5, 50, 140, 230, 320;

%e 6, 24, 42, 60, 114, 132;

%e 7, 70, 133, 322, 511, 700, 1015;

%e 8, 80, 152, 224, 440, 512, 800, 1016;

%e 9, 18, 27, 36, 45, 54, 63, 72, 81;

%t Table[Take[Select[n Range[10000],Total[IntegerDigits[#]]==n&],n],{n,20}] // Flatten (* _Harvey P. Dale_, Sep 16 2019 *)

%Y Cf. A082260, A082261, A082262, A082263, A002998.

%K base,nonn,tabl,look

%O 1,2

%A _Amarnath Murthy_, Apr 12 2003

%E Corrected by Anne Donovan, May 29 2003

%E Corrected and extended by _David Wasserman_, Aug 26 2004