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%I #28 Sep 08 2022 08:46:12
%S 1,33,277,1335,4771,14193,37417,90795,207871,456693,974437,2036655,
%T 4195771,8558073,17337697,34964595,70300471,141070653,282727837,
%U 566179575,1133243251,2267556033,4536394777,9074315835,18150434671,36302985093,72608437717,145219736895
%N a(n) = 541*(2^n - 1) - 5*n^4 - 30*n^3 - 130*n^2 - 375*n.
%C See the first comment of A257448.
%H <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (7,-20,30,-25,11,-2).
%F G.f.: x*(1+26*x+66*x^2+26*x^3+x^4)/(-1+x)^5*(-1+2*x).
%F a(n) = 7*a(n-1) -20*a(n-2) +30*a(n-3) -25*a(n-4) +11*a(n-5) -2*a(n-6) for n>6.
%e This sequence provides the antidiagonal sums of the array:
%e 1, 32, 243, 1024, 3125, 7776, ... A000584
%e 1, 33, 276, 1300, 4425, 12201, ... A000539
%e 1, 34, 310, 1610, 6035, 18236, ... A101092
%e 1, 35, 345, 1955, 7990, 26226, ... A101099
%e 1, 36, 381, 2336, 10326, 36552, ... A254644
%e 1, 37, 418, 2754, 13080, 49632, ... A254682
%e ...
%e See also A254682 (Example field).
%t Table[541 (2^n - 1) - 5 n^4 - 30 n^3 - 130 n^2 - 375 n, {n, 30}]
%t LinearRecurrence[{7,-20,30,-25,11,-2},{1,33,277,1335,4771,14193},30] (* _Harvey P. Dale_, Dec 24 2018 *)
%o (Magma) [541*(2^n-1)-5*n^4-30*n^3-130*n^2-375*n: n in [1..30]]; // _Vincenzo Librandi_, Apr 24 2015
%Y Cf. A000225, A000670, A050488, A208744, A257448, A257449.
%K nonn,easy
%O 1,2
%A _Luciano Ancora_, Apr 23 2015