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 A182119 Table of triangular arguments such that if A002262(14*k) = "r" then the product A182439(k,i + 1) *A182439(k,i + 2) equals "r" + A000217(a(k,i)) for i<4, while a(k,i) = 0 for i>3. 3
 0, 55, 4, 384, 51, 7, 2303, 328, 48, 8, 0, 1943, 287, 47, 10, 0, 0, 1680, 276, 45, 11, 0, 0, 0, 1611, 250, 44, 12, 0, 0, 0, 0, 1445, 239, 43, 13, 0, 0, 0, 0, 0, 1376, 228, 42, 14, 0, 0, 0, 0, 0, 1307, 213, 41, 15 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS The triangular product A000217(a(k,i)) for i < 4 + A002262(14*k) = the product of adjacent terms G(k,i+1)*G(k,i+2) where G is table A182439. The remainder of each row is padded with zeros. However, if for i > 3, a(k,i) were set to equal 7*a(k,i-1) - 7*a(k,i-2) + a(k,i-3) then the relation above would not be limited to i < 4. Also, it is noted that the difference between adjacent rows of the respective elements, depends on the difference between the elements of column 0 in the respective rows. In the Mathematica program below, m is set to 14; however, regardless of it value of m, it is apparent that the series of differences corresponding to a difference of d in column 0, i.e. A(k+1,0) - A(k,0) = d, is defined as follows: D(0) = d, D(1) = - d, D(n) = 6*D(n-1) - D(n-2) -8*d + 4. The sequence of differences corresponding to a difference of 1 or 0 in column 0 form related series A182188 and A182190. The Mathematica program below basically first computes only the nonnegative triangular arguments P. Then it changes at most two of the arguments P in each row k to the corresponding negative value, N = -P -1, in order to obtain the relation a(k,3) = a(k,0) - 7*a(k,1) + 7*a(k,2). LINKS Table of n, a(n) for n=0..53. MATHEMATICA highTri = Compile[{{S1, _Integer}}, Module[{xS0=0, xS1=S1}, While[xS1-xS0*(xS0+1)/2>xS0, xS0++]; xS0]]; overTri = Compile[{{S2, _Integer}}, Module[{xS0=0, xS2=S2}, While[xS2-xS0*(xS0+1)/2>xS0, xS0++]; xS2 - (xS0*(1+xS0)/2)]]; tt = SparseArray[{{12, 1} -> 1, {1, 12} -> 1}]; K1 = 0; m = 14; While[K1<12, J1=highTri[m*K1]; X =2*(m+K1-(J1*2+1)); K2 = 6 m - K1 + X; K3 = 6 K2 - m + X; K4 = 6 K3 - K2 + X; o = overTri[m*K1]; tt[[1, K1+1]] =highTri[m*K1]; tt[[2, K1+1]] = highTri[m*K2-o]; tt[[3, K1+1]] = highTri[K2*K3-o]; tt[[4, K1+1]] = highTri[K3*K4-o]; K1++]; k = 1; While[k<13, z = 1; xx = 99; While[z<5 && xx == 99, If[tt[[1, k]]+ 7 tt[[3, k]] - 7 tt[[2, k]] - tt[[4, k]] == 0, Break[]]; If[z == 1, t = -tt[[z, k]]-1; tt[[z, k]] = t, s = -tt[[z-1, k]]-1; tt[[z-1, k]]=s; t =-tt[[z, k]]-1]; tt[[z, k]] = t; w = 1; While[w<5 && xx == 99, If[tt[[1, k]]+ 7 tt[[3, k]] - 7 tt[[2, k]] - tt[[4, k]] == 0, xx =0; Break[]]; If[w==z, w++]; t=-tt[[w, k]] - 1; tt[[w, k]]=t; If[tt[[1, k]]+ 7 tt[[3, k]] - 7 tt[[2, k]] - tt[[4, k]] == 0, xx =0; Break[], t = -tt[[w, k]] - 1]; tt[[w, k]] = t; w++]; z++]; cc = tt[[1, k]] -6 tt[[2, k]] + tt[[3, k]]; p = 5; While[p < 14-k, tt[[p, k]] = 6 tt[[p-1, k]] - tt[[p-2, k]] + cc; p++]; k++]; a=1; list2 = Reap[While[a<12, b=a; While[b>4, Sow[0]; b--]; While[b>0, Sow[tt[[b, a+1-b]]]; b--]; a++]][[2, 1]]; list2 CROSSREFS Cf. A182439, A182188, A182190 Sequence in context: A218430 A159732 A174946 * A227856 A057965 A083516 Adjacent sequences: A182116 A182117 A182118 * A182120 A182121 A182122 KEYWORD nonn,tabl AUTHOR Kenneth J Ramsey, Apr 12 2012 STATUS approved

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Last modified February 26 17:57 EST 2024. Contains 370352 sequences. (Running on oeis4.)