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%I #25 Apr 14 2022 13:21:52
%S 1,17,190,1770,14931,118587,905920,6742340,49288261,355826757,
%T 2546230050,18106416510,128181315991,904540692527,6368500164580,
%U 44764509392280,314282333570121,2204653080603897,15456046918261510,108310071701877650,758760684298882651
%N Expansion of 1/((1-x)(1-4x)(1-5x)(1-7x)).
%H Vincenzo Librandi, <a href="/A021754/b021754.txt">Table of n, a(n) for n = 0..200</a>
%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (17,-99,223,-140).
%F a(n) = (2*7^(n+3)-9*5^(n+3)+8*4^(n+3)-1)/72. [_Yahia Kahloune_, May 08 2013]
%p A021754:=n->(2*7^(n+3)-9*5^(n+3)+8*4^(n+3)-1)/72: seq(A021754(n), n=0..30); # _Wesley Ivan Hurt_, Apr 18 2017
%t CoefficientList[Series[1 / ((1 - x) (1 - 4 x) (1 - 5 x) (1 - 7 x)), {x, 0, 20}], x] (* _Vincenzo Librandi_, Jul 11 2013 *)
%t LinearRecurrence[{17,-99,223,-140},{1,17,190,1770},30] (* _Harvey P. Dale_, Apr 14 2022 *)
%o (PARI) x='x+O('x^66); Vec(1/((1-x)*(1-4*x)*(1-5*x)*(1-7*x)) ) \\ _Joerg Arndt_, May 08 2013
%K nonn,easy
%O 0,2
%A _N. J. A. Sloane_
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