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Triangle read by rows: the n-th row contains the first n-1 multiples of prime(n) followed by the next multiple that will make the row sum a multiple of n.
3

%I #6 Dec 05 2013 19:56:14

%S 2,3,9,5,10,15,7,14,21,42,11,22,33,44,55,13,26,39,52,65,117,17,34,51,

%T 68,85,102,119,19,38,57,76,95,114,133,228,23,46,69,92,115,138,161,184,

%U 207,29,58,87,116,145,174,203,232,261,435,31,62,93,124,155,186,217,248,279

%N Triangle read by rows: the n-th row contains the first n-1 multiples of prime(n) followed by the next multiple that will make the row sum a multiple of n.

%e 2

%e 3 9

%e 5 10 15

%e 7 14 21 42

%e 11 22 33 44 55

%e 13 26 39 52 65 117

%e 17 34 51 68 85 102 119

%e ...

%o (PARI) for(n=1,20,p=prime(n);for(k=1,n-1,print1(k*p,","));s=p*((n-1)*n)/2;k=n;while(denominator((s+k*p)/n)>1,k++);print(k*p,",")) (Herrgesell)

%Y Cf. A083174, A083175, A083176.

%K nonn,tabl

%O 1,1

%A _Amarnath Murthy_, Apr 26 2003

%E More terms and better description from Lambert Herrgesell (zero815(AT)googlemail.com), Dec 30 2005