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 A143972 Eigentriangle by rows, A143971 * (A108300 * 0^(n-k)); 1<=k<=1 1
 1, 4, 1, 7, 4, 5, 10, 7, 20, 16, 13, 10, 35, 64, 53, 16, 13, 50, 112, 212, 175, 19, 16, 65, 160, 371, 700, 578, 22, 19, 80, 208, 530, 1225, 2312, 1909, 25, 28, 95, 256, 689, 1750, 4046, 7636, 6305, 28, 25, 110, 304, 848, 2275, 5780, 23363, 25220, 20824 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Right border = A108300: (1, 1, 5, 16, 53, 175, 578,...). Row sums = (1, 5, 16, 53, 175, 578,...) = INVERT transform of (1, 4, 7, 10,...). Sum of n-th row terms = rightmost term of next row. Comment in A108300 states that (5, 16, 53, 175,...) is related to the numbers of hydrogen bonds in hydrocarbons. LINKS FORMULA Eigentriangle by rows, A143971 * (A108300 * 0^(n-k)); 1<=k<=1 Triangle A143971 = (1; 4,1; 7,4,1; 10,7,4,1;...). A108300 * 0^(n-k) = an infinite lower triangular matrix with A108300 (1, 1, 5, 16, 53, 175, 578, 1909,...) in the main diagonal and the rest zeros. By rows, = termwise products of n-th row terms of A143971 and n terms of A108300. EXAMPLE First few rows of the triangle = 1; 4, 1; 7, 4, 5; 10, 7, 10, 16; 13, 10, 35, 64, 53; 16, 13, 50, 112, 212, 175; 19, 16, 65, 160, 371, 700, 578; 22, 19, 80, 208, 530, 1225, 2312, 1909; 25, 22, 95, 256, 689, 1750, 4046, 7636, 6305; ... Example: row 4 = (10, 7, 20, 16) = termwise products of (10, 7, 4, 1) and (1, 1, 5, 16) = (10*1, 7*1, 4*5, 1*16), where (10, 7, 4, 1) = row 4 of triangle A143971. CROSSREFS A143971, Cf. A016777, A108300 Sequence in context: A037023 A143971 A016688 * A019651 A262606 A286387 Adjacent sequences:  A143969 A143970 A143971 * A143973 A143974 A143975 KEYWORD nonn,tabl AUTHOR Gary W. Adamson, Sep 06 2008 STATUS approved

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Last modified April 10 21:21 EDT 2021. Contains 342856 sequences. (Running on oeis4.)