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Triangle in which first row is {1}; to get n-th row take first n numbers greater than last number in previous row which are congruent to 1 (mod n).
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%I #2 Mar 30 2012 17:30:44

%S 1,3,5,7,10,13,17,21,25,29,31,36,41,46,51,55,61,67,73,79,85,92,99,106,

%T 113,120,127,134,137,145,153,161,169,177,185,193,199,208,217,226,235,

%U 244,253,262,271,281,291,301,311,321,331,341,351,361,371,375,386,397

%N Triangle in which first row is {1}; to get n-th row take first n numbers greater than last number in previous row which are congruent to 1 (mod n).

%t a = {1}; k = 2; Do[i = 1; While[i < n + 1, If[ Mod[k, n] == 1, a = Append[a, k]; i++ ]; k++ ], {n, 2, 11}]; a

%Y Cf. A071977 & A072467.

%K nonn

%O 1,2

%A _Robert G. Wilson v_, Jun 28 2002