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 A118007 #21 Aug 12 2022 09:26:54 %S A118007 2,3,2,7,4,2,18,14,5,2,47,52,23,6,2,123,194,110,34,7,2,322,724,527, %T A118007 198,47,8,2,843,2702,2525,1154,322,62,9,2,2207,10084,12098,6726,2207, %U A118007 488,79,10,2,5778,37634,57965,39202,15127,3842,702,98,11,2 %N A118007 Triangle, diagonals generated from Lucas polynomials. %C A118007 Leftmost column = A005248, bisection of Lucas sequence A000032. %C A118007 Refer to A084534 for a variation of the Lucas polynomials. %D A118007 Jay Kappraff, "Beyond Measure, A Guided tour Through Nature, Myth and Number", World Scientific, 2002, p. 485 (Table 22.6b). %F A118007 Diagonals are sequences as f(x), x=1,2,3; Lucas polynomials in the format: (2); (x + 2); (x^2 + 4x + 2); (x^3 + 6x^2 + 9x + 2); (x^4 + 8x^3 + 20x^2 + 16x + 2); (x^5 + 10x^4 + 35x^3 + 50x^2 + 25x + 2); ... %F A118007 Diagonals of the triangle are binomial transforms of A118008 rows. %e A118007 First few rows of the triangle: %e A118007 2; %e A118007 3, 2; %e A118007 7, 4, 2; %e A118007 18, 14, 5, 2; %e A118007 47, 52, 23, 6, 2; %e A118007 123, 194, 110, 34, 7, 2; %e A118007 ... %e A118007 For example, 4th diagonal from the right (18, 52, 110, ...) = f(x), x=1,2,3, ...: x^3 + 6x^2 + 9x + 2. %e A118007 (18, 52, 110, ...) = binomial transform of 4th row of A118008: (18, 34, 24, 6). %o A118007 (PARI) TLucas(n,k) = binomial(n-k, k) + binomial(n-k-1, k-1) + (n==0); \\ A084534 %o A118007 pol(n) = Pol(vector(n+1, k, TLucas(2*n,k-1))); %o A118007 T(n,k) = subst(pol(n-k), x, k+1); %o A118007 trgT(nn) = for (n=0, nn, for (k=0, n, print1(T(n,k), ", ")); print); \\ _Michel Marcus_, Aug 12 2022 %Y A118007 Cf. A000032, A005248, A034807, A118008. %Y A118007 Cf. A084534. %K A118007 nonn,tabl %O A118007 0,1 %A A118007 _Gary W. Adamson_, Apr 09 2006 %E A118007 More terms from _Michel Marcus_, Aug 12 2022