A268148
A double binomial sum involving absolute values.
Original entry on oeis.org
0, 8, 768, 30720, 917504, 23592960, 553648128, 12213813248, 257698037760, 5257039970304, 104453604638720, 2031897488130048, 38843546786070528, 731834939447705600, 13618885273168379904, 250760427251989217280, 4574792530279968800768, 82788987402808467652608
Offset: 0
- Colin Barker, Table of n, a(n) for n = 0..800
- Richard P. Brent, Hideyuki Ohtsuka, Judy-anne H. Osborn, Helmut Prodinger, Some binomial sums involving absolute values, arXiv:1411.1477v2 [math.CO], 2016.
- Index entries for linear recurrences with constant coefficients, signature (48,-768,4096).
-
a(n) = sum(k=-n,n, sum(l=-n,n, binomial(2*n, n+k)*binomial(2*n, n+l)*abs(k^2 - l^2)^2));
-
concat(0, Vec(8*x*(1+48*x)/(1-16*x)^3 + O(x^20))) \\ Colin Barker, Feb 11 2016
A268147
A double binomial sum involving absolute values.
Original entry on oeis.org
0, 16, 512, 12288, 262144, 5242880, 100663296, 1879048192, 34359738368, 618475290624, 10995116277760, 193514046488576, 3377699720527872, 58546795155816448, 1008806316530991104, 17293822569102704640, 295147905179352825856, 5017514388048998039552
Offset: 0
- Colin Barker, Table of n, a(n) for n = 0..800
- Richard P. Brent, Hideyuki Ohtsuka, Judy-anne H. Osborn, Helmut Prodinger, Some binomial sums involving absolute values, arXiv:1411.1477v2 [math.CO], 2016.
- Index entries for linear recurrences with constant coefficients, signature (32,-256).
-
a:= proc(n) option remember;
16*`if`(n<2, n, n*a(n-1)/(n-1))
end:
seq(a(n), n=0..20); # Alois P. Heinz, Jan 29 2016
-
Table[n*16^n, {n, 0, 20}] (* Jean-François Alcover, Oct 24 2016 *)
LinearRecurrence[{32,-256},{0,16},20] (* Harvey P. Dale, Jul 19 2018 *)
-
a(n) = sum(k=-n,n, sum(l=-n,n,binomial(2*n, n+k)*binomial(2*n, n+l)*abs(k-l)^2));
-
concat(0, Vec(16*x/(1-16*x)^2 + O(x^20))) \\ Colin Barker, Feb 11 2016
-
a(n)=n*16^n \\ Charles R Greathouse IV, May 10 2016
A268150
A double binomial sum involving absolute values.
Original entry on oeis.org
0, 8, 2496, 177120, 7616000, 255780000, 7410154752, 194544814464, 4760448675840, 110493063252000, 2461297261280000, 53051182041906048, 1113060644163127296, 22833886572836393600, 459594580755139200000, 9100826722891800000000, 177680489488222659379200, 3426237501864596491802400
Offset: 0
-
A268150 := proc(n)
add( add( binomial(2*n,n+k)*binomial(2*n,n+l)*abs(k^2-l^2)^3,l=-n..n),k=-n..n) ;
end proc:
seq(A268150(n),n=0..10) ; # R. J. Mathar, Feb 27 2023
-
a(n) = sum(k=-n,n, sum(l=-n,n, binomial(2*n, n+k)*binomial(2*n, n+l)*abs(k^2 - l^2)^3));
A268152
A double binomial sum involving absolute values.
Original entry on oeis.org
0, 8, 8832, 1228800, 79364096, 3562536960, 129276837888, 4079413624832, 116608362086400, 3096396542509056, 77661255048888320, 1861218099127123968, 42980384518787039232, 962362945373732864000, 20993511648589057622016, 447858123072052742062080, 9371462498278516088373248
Offset: 0
- Colin Barker, Table of n, a(n) for n = 0..800
- Richard P. Brent, Hideyuki Ohtsuka, Judy-anne H. Osborn, Helmut Prodinger, Some binomial sums involving absolute values, arXiv:1411.1477v2 [math.CO], 2016.
- Index entries for linear recurrences with constant coefficients, signature (80,-2560,40960,-327680,1048576).
-
a(n) = sum(k=-n,n,sum(l=-n,n, binomial(2*n, n+k)*binomial(2*n, n+l)*abs(k^2 - l^2)^4));
-
concat(0, Vec(8*x*(1+1024*x+67840*x^2+417792*x^3)/(1-16*x)^5 + O(x^20))) \\ Colin Barker, Feb 11 2016
A166335
Exponential Riordan array [1+x*sinh(x), x].
Original entry on oeis.org
1, 0, 1, 2, 0, 1, 0, 6, 0, 1, 4, 0, 12, 0, 1, 0, 20, 0, 20, 0, 1, 6, 0, 60, 0, 30, 0, 1, 0, 42, 0, 140, 0, 42, 0, 1, 8, 0, 168, 0, 280, 0, 56, 0, 1, 0, 72, 0, 504, 0, 504, 0, 72, 0, 1, 10, 0, 360, 0, 1260, 0, 840, 0, 90, 0, 1
Offset: 0
Triangle begins
1,
0, 1,
2, 0, 1,
0, 6, 0, 1,
4, 0, 12, 0, 1,
0, 20, 0, 20, 0, 1,
6, 0, 60, 0, 30, 0, 1,
0, 42, 0, 140, 0, 42, 0, 1,
8, 0, 168, 0, 280, 0, 56, 0, 1,
0, 72, 0, 504, 0, 504, 0, 72, 0, 1,
10, 0, 360, 0, 1260, 0, 840, 0, 90, 0, 1
-
(* The function RiordanArray is defined in A256893. *)
RiordanArray[1 + # Sinh[#]&, #&, 11, True] // Flatten (* Jean-François Alcover, Jul 19 2019 *)
A268149
A double binomial sum involving absolute values.
Original entry on oeis.org
0, 24, 1120, 33264, 823680, 18475600, 389398464, 7862853600, 153876579840, 2940343837200, 55138611528000, 1018383898440480, 18574619721465600, 335240928272918304, 5996573430996184960, 106438123408375281600, 1876607120325212706816, 32891715945378106711440
Offset: 0
-
a(n) = sum(k=-n,n, sum(l=-n,n, binomial(2*n, n+k)*binomial(2*n, n+l)*abs(k-l)^3));
A268151
A double binomial sum involving absolute values.
Original entry on oeis.org
0, 40, 2816, 104448, 3014656, 76021760, 1761607680, 38520487936, 807453851648, 16389595201536, 324355930193920, 6289206510878720, 119908340078739456, 2254051613498933248, 41865462136036130816, 769575104325070356480, 14019525496019259228160, 253384476596474400997376
Offset: 0
- Colin Barker, Table of n, a(n) for n = 0..800
- Richard P. Brent, Hideyuki Ohtsuka, Judy-anne H. Osborn, Helmut Prodinger, Some binomial sums involving absolute values, arXiv:1411.1477v2 [math.CO], 2016.
- Index entries for linear recurrences with constant coefficients, signature (48,-768,4096).
-
LinearRecurrence[{48,-768,4096},{0,40,2816},20] (* Harvey P. Dale, Apr 28 2022 *)
-
a(n) = sum(k=-n,n, sum(l=-n,n, binomial(2*n, n+k)*binomial(2*n, n+l)*abs(k-l)^4));
-
concat(0, Vec(8*x*(5+112*x)/(1-16*x)^3 + O(x^20))) \\ Colin Barker, Feb 11 2016
Showing 1-7 of 7 results.
Comments