This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A196486 #16 Oct 30 2018 10:31:02
%S A196486 1,7,5,1,25,23,19,11,79,77,73,65,49,17,241,239,235,227,211,179,115,
%T A196486 727,725,721,713,697,665,601,473,217,2185,2183,2179,2171,2155,2123,
%U A196486 2059,1931,1675,1163,139,6559,6557,6553,6545,6529,6497,6433,6305,6049,5537
%N A196486 Irregular triangle 3^n-2^m.
%C A196486 Each n-th row consists of A056576(n) terms, the first term is 3^n-2, n-th term is 3^n-2^n=A001047(n), and the last term is A056577(n).
%C A196486 T(n,k) = A227048(n,A056576(n)-k) for k = 1..A056576(n). - _Reinhard Zumkeller_, Jun 30 2013
%H A196486 T. D. Noe, <a href="/A196486/b196486.txt">Rows n = 1..100 of triangle, flattened</a>
%e A196486 Rows are:
%e A196486 n=1: 1
%e A196486 n=2: 7,5,1
%e A196486 n=3: 25,23,19,11
%e A196486 n=4: 79,77,73,65,49,17
%e A196486 n=5: 241,239,235,227,211,179,115.
%t A196486 Flatten[Table[3^k - 2^m, {k, 10}, {m, Floor[Log[2, 3^k]]}]]
%o A196486 (Haskell)
%o A196486 a196486 n k = a196486_tabf !! (n-1) !! (k-1)
%o A196486 a196486_row n = a196486_tabf !! (n-1)
%o A196486 a196486_tabf = map (tail . reverse) $ tail a227048_tabf
%o A196486 -- _Reinhard Zumkeller_, Jun 30 2013
%Y A196486 Cf. A001047, A056576, A056577.
%K A196486 nonn,tabf
%O A196486 1,2
%A A196486 _Zak Seidov_, Oct 03 2011