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A257450
a(n) = 541*(2^n - 1) - 5*n^4 - 30*n^3 - 130*n^2 - 375*n.
2
1, 33, 277, 1335, 4771, 14193, 37417, 90795, 207871, 456693, 974437, 2036655, 4195771, 8558073, 17337697, 34964595, 70300471, 141070653, 282727837, 566179575, 1133243251, 2267556033, 4536394777, 9074315835, 18150434671, 36302985093, 72608437717, 145219736895
OFFSET
1,2
COMMENTS
See the first comment of A257448.
FORMULA
G.f.: x*(1+26*x+66*x^2+26*x^3+x^4)/(-1+x)^5*(-1+2*x).
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.
EXAMPLE
This sequence provides the antidiagonal sums of the array:
1, 32, 243, 1024, 3125, 7776, ... A000584
1, 33, 276, 1300, 4425, 12201, ... A000539
1, 34, 310, 1610, 6035, 18236, ... A101092
1, 35, 345, 1955, 7990, 26226, ... A101099
1, 36, 381, 2336, 10326, 36552, ... A254644
1, 37, 418, 2754, 13080, 49632, ... A254682
...
See also A254682 (Example field).
MATHEMATICA
Table[541 (2^n - 1) - 5 n^4 - 30 n^3 - 130 n^2 - 375 n, {n, 30}]
LinearRecurrence[{7, -20, 30, -25, 11, -2}, {1, 33, 277, 1335, 4771, 14193}, 30] (* Harvey P. Dale, Dec 24 2018 *)
PROG
(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
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Luciano Ancora, Apr 23 2015
STATUS
approved