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 1-5 of 5 results.

A048770 Partial sums of A048694.

Original entry on oeis.org

1, 8, 23, 60, 149, 364, 883, 2136, 5161, 12464, 30095, 72660, 175421, 423508, 1022443, 2468400, 5959249, 14386904, 34733063, 83853036, 202439141, 488731324, 1179901795, 2848534920, 6876971641, 16602478208, 40081928063
Offset: 0

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Author

Keywords

Crossrefs

Programs

  • Mathematica
    Accumulate[LinearRecurrence[{2,1},{1,7},40]] (* Harvey P. Dale, Jul 22 2011 *)
    LinearRecurrence[{3, -1, -1},{1, 8, 23},27] (* Ray Chandler, Aug 03 2015 *)

Formula

a(n) = ((7+4*sqrt(2))*(1+sqrt(2))^n-(7-4*sqrt(2))*(1-sqrt(2))^n)/(2*sqrt(2))-3.
a(n) = 2*a(n-1)+a(n-2)+6 with n>1, a(0)=1, a(1)=8.
a(n) = 3*a(n-1)-a(n-2)-a(n-3). G.f.: (1+5*x)/((1-x)*(1-2*x-x^2)). - Colin Barker, Jun 23 2012
a(n) = 3*A000129(n)+4*A000129(n+1)-3. - R. J. Mathar, Sep 27 2012

Extensions

More terms from James Sellers, Jun 20 2000

A163864 a(n) = 2*a(n-2) for n > 2; a(1) = 1, a(2) = 6.

Original entry on oeis.org

1, 6, 2, 12, 4, 24, 8, 48, 16, 96, 32, 192, 64, 384, 128, 768, 256, 1536, 512, 3072, 1024, 6144, 2048, 12288, 4096, 24576, 8192, 49152, 16384, 98304, 32768, 196608, 65536, 393216, 131072, 786432, 262144, 1572864, 524288, 3145728, 1048576, 6291456
Offset: 1

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Author

Klaus Brockhaus, Aug 05 2009

Keywords

Comments

Interleaving of A000079 and A007283 without initial 3.
Binomial transform is A048694, second binomial transform is A163613, third binomial transform is A163614, fourth binomial transform is A163615, fifth binomial transform is A163616, sixth binomial transform is A081183 without initial 0.

Crossrefs

Cf. A000079 (powers of 2), A007283 (3*2^n), A048694, A163613, A163614, A163615, A163616, A081183.

Programs

  • Magma
    [ n le 2 select 5*n-4 else 2*Self(n-2): n in [1..42] ];
    
  • Mathematica
    LinearRecurrence[{0, 2}, {1, 6, 2, 12}, 50] (* G. C. Greubel, Aug 06 2017 *)
  • PARI
    x='x+O('x^50); Vec(x*(1+6*x)/(1-2*x^2)) \\ G. C. Greubel, Aug 06 2017

Formula

a(n) = (2+(-1)^n)*2^(1/4*(2*n-1+(-1)^n)).
G.f.: x*(1+6*x)/(1-2*x^2).

A163613 a(n) = ((1 + 3*sqrt(2))*(2 + sqrt(2))^n + (1 - 3*sqrt(2))*(2 - sqrt(2))^n)/2.

Original entry on oeis.org

1, 8, 30, 104, 356, 1216, 4152, 14176, 48400, 165248, 564192, 1926272, 6576704, 22454272, 76663680, 261746176, 893657344, 3051137024, 10417233408, 35566659584, 121432171520, 414595366912, 1415517124608, 4832877764608
Offset: 0

Views

Author

Al Hakanson (hawkuu(AT)gmail.com), Aug 01 2009

Keywords

Comments

Binomial transform of A048694. Second binomial transform of A163864. Inverse binomial transform of A163614.

Crossrefs

Cf. A048694, A163864 (1, 6, 2, 12, 4, 24, ...), A163614.

Programs

  • Magma
    Z:= PolynomialRing(Integers()); N:=NumberField(x^2-2); S:=[ ((1+3*r)*(2+r)^n+(1-3*r)*(2-r)^n)/2: n in [0..23] ]; [ Integers()!S[j]: j in [1..#S] ]; // Klaus Brockhaus, Aug 06 2009
    
  • Mathematica
    LinearRecurrence[{4, -2}, {1, 8}, 50] (* G. C. Greubel, Jul 30 2017 *)
  • PARI
    x='x+O('x^50); Vec((1+4*x)/(1-4*x+2*x^2)) \\ G. C. Greubel, Jul 30 2017

Formula

a(n) = 4*a(n-1) - 2*a(n-2) for n > 1; a(0) = 1, a(1) = 8.
G.f.: (1+4*x)/(1-4*x+2*x^2).
E.g.f.: exp(2*x)*( cosh(sqrt(2)*x) + 3*sqrt(2)*sinh(sqrt(2)*x) ). - G. C. Greubel, Jul 30 2017

Extensions

Edited and extended beyond a(5) by Klaus Brockhaus, Aug 06 2009

A048772 Partial sums of A048696.

Original entry on oeis.org

1, 10, 29, 76, 189, 462, 1121, 2712, 6553, 15826, 38213, 92260, 222741, 537750, 1298249, 3134256, 7566769, 18267802, 44102381, 106472572, 257047533, 620567646, 1498182833
Offset: 0

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Author

Keywords

Crossrefs

Programs

  • Haskell
    a048772 n = a048772_list !! n
    a048772_list = scanl1 (+) a048696_list
    -- Reinhard Zumkeller, Dec 15 2013
    
  • Mathematica
    Accumulate[LinearRecurrence[{2,1},{1,9},30]] (* or *) LinearRecurrence[ {3,-1,-1},{1,10,29},30] (* Harvey P. Dale, Apr 20 2012 *)
  • PARI
    a(n)=([0,1,0; 0,0,1; -1,-1,3]^n*[1;10;29])[1,1] \\ Charles R Greathouse IV, Feb 10 2017

Formula

a(n)=2*a(n-1)+a(n-2)+8; a(0)=1, a(1)=10.
a(n)=[ {(9+5*sqrt(2))(1+sqrt(2))^n - (9-5*sqrt(2))(1-sqrt(2))^n}/2*sqrt(2) ]-4.
a(0)=1, a(1)=10, a(2)=29, a(n)=3*a(n-1)-a(n-2)-a(n-3). - Harvey P. Dale, Apr 20 2012
G.f. ( 1+7*x ) / ( (x-1)*(x^2+2*x-1) ). a(n)=A048739(n)+7*A048739(n-1). - R. J. Mathar, Nov 08 2012

A048771 Partial sums of A048695.

Original entry on oeis.org

1, 9, 26, 68, 169, 413, 1002, 2424, 5857, 14145, 34154, 82460, 199081, 480629, 1160346, 2801328, 6763009, 16327353, 39417722, 95162804, 229743337, 554649485, 1339042314, 3232734120, 7804510561, 18841755249, 45488021066, 109817797388, 265123615849
Offset: 0

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Author

Keywords

Examples

			a(n)=[ {(8+(9/2)*sqrt(2))(1+sqrt(2))^n -(8-(9/2)*sqrt(2))(1-sqrt(2))^n}/ 2*sqrt(2) ]-7/2.
		

Crossrefs

Programs

  • Mathematica
    Table[6*Fibonacci[n, 2] + Fibonacci[n+1, 2], {n, 0, 22}] // Accumulate (* Jean-François Alcover, Mar 25 2013 *)
    Accumulate[LinearRecurrence[{2,1},{1,8},40]] (* or *) LinearRecurrence[ {3,-1,-1},{1,9,26},40] (* Harvey P. Dale, May 01 2013 *)

Formula

a(n)=2*a(n-1)+a(n-1)+7; a(0)=1, a(1)=9.
G.f. ( 1+6*x ) / ( (x-1)*(x^2+2*x-1) ). a(n)=A048739(n)+6*A048739(n-1). - R. J. Mathar, Nov 08 2012
a(0)=1, a(1)=9, a(2)=26, a(n)=3*a(n-1)-a(n-2)-a(n-3). - Harvey P. Dale, May 01 2013

Extensions

More terms from Harvey P. Dale, May 01 2013
Showing 1-5 of 5 results.