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A073915 Triangle read by rows in which the n-th row contains the first n numbers with n divisors.

%I A073915 #22 Dec 05 2013 19:55:32
%S A073915 1,2,3,4,9,25,6,8,10,14,16,81,625,2401,14641,12,18,20,28,32,44,64,729,
%T A073915 15625,117649,1771561,4826809,24137569,24,30,40,42,54,56,66,70,36,100,
%U A073915 196,225,256,441,484,676,1089,48,80,112,162,176,208,272,304,368,405
%N A073915 Triangle read by rows in which the n-th row contains the first n numbers with n divisors.
%C A073915 The first row contains the 1. The 2nd row contains the beginning of A000040. The 3rd contains the beginning of A001248, the 4th through 7th A030513 to A030516. The 8th through 20th rows come from A030626 to A030638. - _R. J. Mathar_, Mar 23 2007
%H A073915 T. D. Noe, <a href="/A073915/b073915.txt">Rows n = 1..100 of triangle, flattened</a>
%e A073915 1;
%e A073915 2,3;
%e A073915 4,9,25;
%e A073915 6,8,10,14;
%e A073915 16,81,625,2401,14641;
%e A073915 ...
%t A073915 d = Table[Length[Divisors[n]], {n, 2000}]; t = {}; n = 0; ok = True; While[ok, n++; If[PrimeQ[n], AppendTo[t, Prime[Range[n]]^(n - 1)], c = Flatten[Position[d, n, 1, n]]; If[Length[c] >= n, AppendTo[t, c], ok = False]]]; Flatten[t] (* _T. D. Noe_, Jun 23 2013 *)
%Y A073915 Cf. A073916.
%K A073915 nonn,tabl
%O A073915 1,2
%A A073915 _Amarnath Murthy_, Aug 18 2002
%E A073915 Corrected and extended by _Sascha Kurz_, Jan 28 2003