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Array read by upward antidiagonals: Niven (or Harshad) numbers arranged in rows by their digit sums.
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%I #28 Jul 14 2014 12:48:59

%S 1,2,10,3,20,100,4,12,110,1000,5,40,21,200,10000,6,50,112,30,1010,

%T 100000,7,24,140,220,102,1100,1000000,8,70,42,230,400,111,2000,

%U 10000000,9,80,133,60,320,1012,120,10010,100000000,190,18,152,322,114,410,1120,201,10100,1000000000

%N Array read by upward antidiagonals: Niven (or Harshad) numbers arranged in rows by their digit sums.

%C The n-th row contains in increasing order all multiples of n with digit sum n.

%C See A005349 for definitions and references.

%H Alois P. Heinz, <a href="/A245062/b245062.txt">Antidiagonals n = 1..70, flattened</a>

%H Eric W. Weisstein, <a href="http://mathworld.wolfram.com/HarshadNumber.html">Harshad Number</a>, from MathWorld.

%e Array begins as:

%e 1 10 100 1000 10000 100000 1000000 10000000 100000000 1000000000

%e 2 20 110 200 1010 1100 2000 10010 10100 11000

%e 3 12 21 30 102 111 120 201 210 300

%e 4 40 112 220 400 1012 1120 1300 2020 2200

%e 5 50 140 230 320 410 500 1040 1130 1220

%e 6 24 42 60 114 132 150 204 222 240

%e 7 70 133 322 511 700 1015 1141 1204 1330

%e 8 80 152 224 440 512 800 1016 1160 1232

%e 9 18 27 36 45 54 63 72 81 90

%e 190 280 370 460 550 640 730 820 910 1090

%Y Cf. A002998 (column 1), A245065 (column 2).

%Y Cf. A011557 (row 1), A069537 (row 2), A052217 (row 3), A063997 (row 4), A069540 (row 5), A062768 (row 6), A063416 (row 7), A069543 (row 8), A052223 (row 9).

%Y Cf. A082260 (main diagonal).

%Y Cf. A007953, A005349 (Niven or Harshad numbers).

%Y Cf. A082259.

%K nonn,base,tabl

%O 1,2

%A _L. Edson Jeffery_, Jul 10 2014