%I #24 Sep 24 2024 06:18:34
%S 1,1807,21883,100801,303829,720931,1466767,2680693,4526761,7193719,
%T 10895011,15868777,22377853,30709771,41176759,54115741,69888337,
%U 88880863,111504331,138194449,169411621,205640947,247392223,295199941
%N a(n) = 1 + 21 n + 168 n^2 + 588 n^3 + 1029 n^4.
%C All terms == 1 (mod 21). - _Robert Israel_, Aug 11 2017
%H Robert Israel, <a href="/A134155/b134155.txt">Table of n, a(n) for n = 0..10000</a>
%H <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (5,-10,10,-5,1).
%F a(n) = (3*(7*n + 1)^4 + 6*(7*n + 1)^2 - 3*(7*n + 1) + 1)/7.
%F G.f.: -(1+1802*x+12858*x^2+9446*x^3+589*x^4)/(-1+x)^5. - _R. J. Mathar_, Nov 14 2007
%p seq( 1 + 21*n + 168*n^2 + 588*n^3 + 1029*n^4,n=0..30); # _Robert Israel_, Aug 11 2017
%t Table[1 + 21 n + 168 n^2 + 588 n^3 + 1029 n^4,{n,0,50}]
%t LinearRecurrence[{5,-10,10,-5,1},{1,1807,21883,100801,303829},30] (* _Harvey P. Dale_, Aug 29 2021 *)
%o (PARI) a(n)=1+21*n+168*n^2+588*n^3+1029*n^4 \\ _Charles R Greathouse IV_, Oct 21 2022
%Y Cf. A119617, A134153, A134154, A134158.
%K nonn,easy
%O 0,2
%A _Artur Jasinski_, Oct 10 2007