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 A206819 Riordan array (1/(1-10*x-10*x^2), x/(1-10*x-10*x^2)). 2
 1, 10, 1, 90, 20, 1, 800, 280, 30, 1, 7100, 3400, 570, 40, 1, 63000, 38300, 8800, 960, 50, 1, 559000, 412000, 120600, 18000, 1450, 60, 1, 4960000, 4296000, 1530000, 291000, 32000, 2040, 70, 1 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Row sums are A000042(n+1). Subtriangle of triangle given by (0, 10, -1, 1, 0, 0, 0, 0, 0, 0, 0, ...) DELTA (1, 0, 0, 0, 0, 0, 0, 0, 0, 0, ...) where DELTA is the operator defined in A084938. LINKS FORMULA T(n,k) = 10*T(n-1,k) - 10*T(n-2,k) + T(n-1,k-1). G.f.: 1/(1-10*x+10*x^2-y*x). Sum_{k, 0<=k} T(n,k)*x^k = A178869(n+1), A057086(n), A000042(n+1) for x = -1, 0, 1 respectively. EXAMPLE Triangle begins : 1 10, 1 90, 20, 1 800, 280, 30, 1 7100, 3400, 570, 40, 1 63000, 38300, 8800, 960, 50, 1 559000, 412000, 120600, 18000, 1450, 60, 1 4960000, 4296000, 1530000, 291000, 32000, 2040, 70, 1 Triangle (0, 10, -1, 1, 0, 0, 0, ...) DELTA (1, 0, 0, 0, 0, 0, 0, 0, ...) begins : 1 0, 1 0, 10, 1 0, 90, 20, 1 0, 800, 280, 30, 1 0, 7100, 3400, 570, 40, 1 ... CROSSREFS Cf. A101950, A178865, Sequence in context: A009227 A305996 A030526 * A178865 A164881 A276379 Adjacent sequences:  A206816 A206817 A206818 * A206820 A206821 A206822 KEYWORD easy,nonn,tabl AUTHOR Philippe Deléham, Feb 12 2012 STATUS approved

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Last modified March 20 15:43 EDT 2019. Contains 321345 sequences. (Running on oeis4.)