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A077320 Triangle in which n-th row contains n smallest multiples of the n-th prime.

%I A077320 #22 May 05 2019 18:41:31
%S A077320 2,3,6,5,10,15,7,14,21,28,11,22,33,44,55,13,26,39,52,65,78,17,34,51,
%T A077320 68,85,102,119,19,38,57,76,95,114,133,152,23,46,69,92,115,138,161,184,
%U A077320 207,29,58,87,116,145,174,203,232,261,290
%N A077320 Triangle in which n-th row contains n smallest multiples of the n-th prime.
%C A077320 0. A000040 (primes) gives initial terms of rows.
%C A077320 1. A033286 contains the final terms of rows.
%C A077320 2. Sum of the n-th row = prime(n)*A000217(n), by definition.
%C A077320 3. a(A000217(n) + 1) = prime(n+1), by definition.
%H A077320 Ivan Neretin, <a href="/A077320/b077320.txt">Table of n, a(n) for n = 1..8128</a>
%F A077320 T(n,k) = k*prime(n) with 1 <= k <= n. - _Bruno Berselli_, Sep 05 2017
%e A077320 From _Bruno Berselli_, Sep 05 2017: (Start)
%e A077320 Triangle begins:
%e A077320    2;
%e A077320    3, 6;
%e A077320    5, 10,  15;
%e A077320    7, 14,  21,  28;
%e A077320   11, 22,  33,  44,  55;
%e A077320   13, 26,  39,  52,  65,  78;
%e A077320   17, 34,  51,  68,  85, 102, 119;
%e A077320   19, 38,  57,  76,  95, 114, 133, 152;
%e A077320   23, 46,  69,  92, 115, 138, 161, 184, 207;
%e A077320   29, 58,  87, 116, 145, 174, 203, 232, 261, 290;
%e A077320   31, 62,  93, 124, 155, 186, 217, 248, 279, 310, 341;
%e A077320   37, 74, 111, 148, 185, 222, 259, 296, 333, 370, 407, 444;
%e A077320   41, 82, 123, 164, 205, 246, 287, 328, 369, 410, 451, 492, 533;
%e A077320   43, 86, 129, 172, 215, 258, 301, 344, 387, 430, 473, 516, 559, 602, etc.
%e A077320 (End)
%t A077320 Table[Prime[n]*Range[n], {n, 10}] // Flatten (* _Ivan Neretin_, May 02 2019 *)
%Y A077320 Cf. A000040, A000217, A033286.
%Y A077320 Row sums give A196421. - _Omar E. Pol_, Mar 12 2012
%K A077320 nonn,tabl,easy
%O A077320 1,1
%A A077320 _Amarnath Murthy_, Nov 04 2002