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A133821 Triangle whose rows are sequences of increasing fourth powers: 1; 1,16; 1,16,81; ... .

%I A133821 #14 Mar 29 2020 20:20:57
%S A133821 1,1,16,1,16,81,1,16,81,256,1,16,81,256,625,1,16,81,256,625,1296,1,16,
%T A133821 81,256,625,1296,2401,1,16,81,256,625,1296,2401,4096,1,16,81,256,625,
%U A133821 1296,2401,4096,6561,1,16,81,256,625,1296,2401,4096,6561,10000
%N A133821 Triangle whose rows are sequences of increasing fourth powers: 1; 1,16; 1,16,81; ... .
%C A133821 Reading the triangle by rows produces the sequence 1,1,16,1,16,81,1,16,81,256,..., analogous to A002260.
%H A133821 Reinhard Zumkeller, <a href="/A133821/b133821.txt">Rows n = 1..120 of triangle, flattened</a>
%F A133821 O.g.f.: (1+11qx+11q^2x^2+q^3x^3)/((1-x)(1-qx)^5) = 1 + x(1 + 16q) + x^2(1 + 16q + 81q^2) + ... . Cf. 4th row of A008292.
%e A133821 Triangle starts
%e A133821 1;
%e A133821 1, 16;
%e A133821 1, 16; 81;
%e A133821 1, 16, 81, 256;
%e A133821 1, 16, 81, 256, 625;
%t A133821 Module[{nn=10,fp},fp=Range[(nn(nn+1))/2]^4;Table[TakeList[fp,{n}],{n,nn}]]//Flatten (* Requires Mathematica version 11 or later *) (* _Harvey P. Dale_, Mar 29 2020 *)
%o A133821 (Haskell)
%o A133821 a133821 n k = a133821_tabl !! (n-1) !! (k-1)
%o A133821 a133821_row n = a133821_tabl !! (n-1)
%o A133821 a133821_tabl = map (`take` (tail a000583_list)) [1..]
%o A133821 -- _Reinhard Zumkeller_, Nov 11 2012
%Y A133821 Cf. A000538 (row sums), A002260, A133819, A133820, A133824.
%K A133821 easy,nonn,tabl
%O A133821 1,3
%A A133821 _Peter Bala_, Sep 25 2007
%E A133821 Offset changed by _Reinhard Zumkeller_, Nov 11 2012