cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-6 of 6 results.

A175110 a(n) = ((2*n+1)^4+1)/2.

Original entry on oeis.org

1, 41, 313, 1201, 3281, 7321, 14281, 25313, 41761, 65161, 97241, 139921, 195313, 265721, 353641, 461761, 592961, 750313, 937081, 1156721, 1412881, 1709401, 2050313, 2439841, 2882401, 3382601, 3945241, 4575313, 5278001, 6058681
Offset: 0

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Author

R. J. Mathar, Feb 13 2010

Keywords

Comments

Binomial transform of 1,40,232,384,192,0,0,.. (0 continued). Convolution of the finite sequence 1,36,118,36,1 with A000332, dropping zeros.
Hypotenuse of Pythagorean triangles with smallest side a square: A016754(n)^2 + (a(n)-1)^2 = a(n)^2. - Martin Renner, Nov 12 2011
a(n) is also the first integer in a sum of (2*n + 1)^4 consecutive integers that equal (2*n + 1)^8. See A016756 and A016760. - Patrick J. McNab, Dec 26 2016

References

  • Albert H. Beiler, Recreations in the theory of numbers, New York: Dover, (2nd ed.) 1966, p. 106, table 54.

Crossrefs

Cf. A000332, A016756, A016760. Partial sums of A117216.

Programs

  • Magma
    I:=[1, 41, 313, 1201, 3281]; [n le 5 select I[n] else 5*Self(n-1) - 10*Self(n-2) + 10*Self(n-3) - 5*Self(n-4) + Self(n-5): n in [1..40]]; // Vincenzo Librandi, Dec 19 2012
    
  • Maple
    A175110:=n->((2*n+1)^4+1)/2: seq(A175110(n), n=0..50); # Wesley Ivan Hurt, Apr 13 2017
  • Mathematica
    CoefficientList[Series[(1 + 36*x + 118*x^2 + 36*x^3 + x^4)/(1-x)^5, {x, 0, 40}], x] (* Vincenzo Librandi, Dec 19 2012 *)
    Table[((2 n + 1)^4 + 1)/2, {n, 0, 29}] (* Michael De Vlieger, Dec 26 2016 *)
    LinearRecurrence[{5,-10,10,-5,1},{1,41,313,1201,3281},40] (* Harvey P. Dale, Jan 01 2022 *)
  • PARI
    a(n)=((2*n+1)^4+1)/2 \\ Charles R Greathouse IV, Oct 16 2015

Formula

a(n) = 5*a(n-1) -10*a(n-2) +10*a(n-3) -5*a(n-4) +a(n-5).
G.f.: (1+36*x+118*x^2+36*x^3+x^4)/ (1-x)^5.
a(n)-a(n-1) = A117216(n).
a(n) = 8*A001844(n) * A000217(n) + 1 = 8*A219086(n) + 1. - Bruce J. Nicholson, Apr 13 2017

A016952 a(n) = (6*n + 3)^8.

Original entry on oeis.org

6561, 43046721, 2562890625, 37822859361, 282429536481, 1406408618241, 5352009260481, 16815125390625, 45767944570401, 111429157112001, 248155780267521, 513798374428641, 1001129150390625, 1853020188851841, 3282116715437121, 5595818096650401, 9227446944279201
Offset: 0

Views

Author

Keywords

Crossrefs

Programs

  • Magma
    [(6*n+3)^8: n in [0..40]]; // Vincenzo Librandi, May 05 2011
  • Mathematica
    a[n_] := (6*n + 3)^8; Array[a, 50, 0] (* Amiram Eldar, Mar 30 2022 *)

Formula

From Amiram Eldar, Mar 30 2022: (Start)
a(n) = A016945(n)^8 = A016946(n)^4 = A016948(n)^2.
a(n) = 3^8*A016760(n).
Sum_{n>=0} 1/a(n) = 17*Pi^8/1058158080. (End)

A016832 a(n) = (4*n + 2)^8.

Original entry on oeis.org

256, 1679616, 100000000, 1475789056, 11019960576, 54875873536, 208827064576, 656100000000, 1785793904896, 4347792138496, 9682651996416, 20047612231936, 39062500000000, 72301961339136, 128063081718016, 218340105584896, 360040606269696, 576480100000000, 899194740203776
Offset: 0

Views

Author

Keywords

Crossrefs

Programs

Formula

From Harvey P. Dale, May 20 2011: (Start)
a(0)=256, a(1)=1679616, a(2)=100000000, a(3)=1475789056, a(4)=11019960576, a(5)=54875873536, a(6)=208827064576, a(7)=656100000000, a(8)=1785793904896, a(n) = 9*a(n-1) - 36*a(n-2) + 84*a(n-3) - 126*a(n-4) + 126*a(n-5) - 84*a(n-6) + 36*a(n-7) - 9*a(n-8) + a(n-9).
G.f.: -((256*(1 + 6552*x + 331612*x^2 + 2485288*x^3 + 4675014*x^4 + 2485288*x^5 + 331612*x^6 + 6552*x^7 + x^8))/(-1+x)^9). (End)
From Amiram Eldar, Apr 21 2023: (Start)
a(n) = A016825(n)^8.
a(n) = 2^8*A016760(n).
Sum_{n>=0} 1/a(n) = 17*Pi^8/41287680. (End)

A016748 a(n) = (2*n)^8.

Original entry on oeis.org

0, 256, 65536, 1679616, 16777216, 100000000, 429981696, 1475789056, 4294967296, 11019960576, 25600000000, 54875873536, 110075314176, 208827064576, 377801998336, 656100000000, 1099511627776, 1785793904896, 2821109907456, 4347792138496, 6553600000000, 9682651996416
Offset: 0

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Author

Keywords

Crossrefs

Programs

  • Magma
    [(2*n)^8: n in [0..20]]; // Vincenzo Librandi, Sep 05 2011
    
  • Maple
    A016748:=n->(2*n)^8; seq(A016748(n), n=0..50); # Wesley Ivan Hurt, Nov 15 2013
  • Mathematica
    Table[(2n)^8, {n,0,50}] (* Wesley Ivan Hurt, Nov 15 2013 *)
    (2*Range[0,20])^8 (* or *) LinearRecurrence[{9,-36,84,-126,126,-84,36, -9, 1}, {0,256 ,65536, 1679616, 16777216, 100000000, 429981696, 1475789056, 4294967296}, 20] (* Harvey P. Dale, Jun 14 2016 *)
  • PARI
    vector(30, n, n--; (2*n)^8) \\ G. C. Greubel, Sep 15 2018

Formula

a(n) = 256*A001016(n) = A001016(A005843(n)). - Michel Marcus, Nov 16 2013
G.f.: 256*x*(1+x)*(x^6 + 246*x^5 + 4047*x^4 + 11572*x^3 + 4047*x^2 + 246*x + 1) / (1-x)^9. - R. J. Mathar, May 01 2015
From Amiram Eldar, Oct 11 2020: (Start)
Sum_{n>=1} 1/a(n) = Pi^8/2419200.
Sum_{n>=1} (-1)^(n+1)/a(n) = 127*Pi^8/309657600. (End)

A017120 a(n) = (8*n + 4)^8.

Original entry on oeis.org

65536, 429981696, 25600000000, 377801998336, 2821109907456, 14048223625216, 53459728531456, 167961600000000, 457163239653376, 1113034787454976, 2478758911082496, 5132188731375616, 10000000000000000, 18509302102818816, 32784148919812096, 55895067029733376
Offset: 0

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Author

Keywords

Crossrefs

Programs

Formula

G.f.: -65536*(1 + 6552*x + 331612*x^2 + 2485288*x^3 + 4675014*x^4 + 2485288*x^5 + 331612*x^6 + 6552*x^7 + x^8)/(x-1)^9. - R. J. Mathar, May 08 2015
From Amiram Eldar, Apr 25 2023: (Start)
a(n) = A017113(n)^8.
a(n) = 2^8*A016832(n) = 2^16*A016760(n).
Sum_{n>=0} 1/a(n) = 17*Pi^8/10569646080. (End)

A017336 a(n) = (10*n + 5)^8.

Original entry on oeis.org

390625, 2562890625, 152587890625, 2251875390625, 16815125390625, 83733937890625, 318644812890625, 1001129150390625, 2724905250390625, 6634204312890625, 14774554437890625, 30590228625390625, 59604644775390625, 110324037687890625, 195408755062890625, 333160561500390625
Offset: 0

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Author

Keywords

Crossrefs

Programs

Formula

G.f.: -((390625*(x^8 + 6552*x^7 + 331612*x^6 + 2485288*x^5 + 4675014*x^4 + 2485288*x^3 + 331612*x^2 + 6552*x + 1))/(x-1)^9). - Harvey P. Dale, Nov 02 2011
From Amiram Eldar, Apr 18 2023: (Start)
a(n) = A017329(n)^8.
a(n) = 5^8 * A016760(n).
Sum_{n>=0} 1/a(n) = 17*Pi^8/63000000000. (End)
Showing 1-6 of 6 results.