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 1-10 of 10 results.

A177116 Partial sums of round(n^2/11).

Original entry on oeis.org

0, 0, 0, 1, 2, 4, 7, 11, 17, 24, 33, 44, 57, 72, 90, 110, 133, 159, 188, 221, 257, 297, 341, 389, 441, 498, 559, 625, 696, 772, 854, 941, 1034, 1133, 1238, 1349, 1467, 1591, 1722, 1860, 2005, 2158, 2318, 2486, 2662, 2846, 3038, 3239, 3448, 3666, 3893
Offset: 0

Views

Author

Mircea Merca, Dec 09 2010

Keywords

Comments

The round function, also called the nearest integer function, is defined here by round(x)=floor(x+1/2).
There are several sequences of integers of the form round(n^2/k) for whose partial sums we can establish identities as following (only for k = 2, ..., 9, 11, 12, 13, 16, 17, 19, 20, 28, 29, 36, 44).

Examples

			a(11) = 0 + 0 + 0 + 1 + 1 + 2 + 3 + 4 + 6 + 7 + 9 + 11 = 44.
		

Crossrefs

Cf. A173690 (k=5), A173691 (k=6), A173722 (k=8), A177100 (k=9), A181120 (k=12).

Programs

  • Maple
    seq(round((2*n^3+3*n^2-11*n)/66),n=0..50)
  • Mathematica
    Accumulate[Round[Range[0,50]^2/11]] (* or *) LinearRecurrence[{3,-3,1,0,0,0,0,0,0,0,1,-3,3,-1},{0,0,0,1,2,4,7,11,17,24,33,44,57,72},60] (* Harvey P. Dale, Dec 10 2014 *)
  • PARI
    a(n)=(2*n^3+3*n^2-11*n+18)\66 \\ Charles R Greathouse IV, Oct 07 2015

Formula

a(n) = round((n-2)*(n+3)*(2*n+1)/66).
a(n) = floor((2*n^3 + 3*n^2 - 11*n + 18)/66).
a(n) = ceiling((2*n^3 + 3*n^2 - 11*n - 30)/66).
a(n) = round(n*(2*n^2 + 3*n - 11)/66).
a(n) = a(n-11) + (n+1)*(n-11) + 44, n > 10.
a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) + a(n-11) - 3*a(n-12) + 3*a(n-13) - a(n-14). - R. J. Mathar, Dec 10 2010
G.f.: x^3 *(1+x) *(x^2-x+1) *(x^4-x^3+x^2-x+1) / ( (x^10 + x^9 + x^8 + x^7 + x^6 + x^5 + x^4 + x^3 + x^2 + x + 1) *(x-1)^4 ). - R. J. Mathar, Dec 10 2010 [Typo fixed by Colin Barker, Oct 10 2012]

A177176 Partial sums of round(n^2/13).

Original entry on oeis.org

0, 0, 0, 1, 2, 4, 7, 11, 16, 22, 30, 39, 50, 63, 78, 95, 115, 137, 162, 190, 221, 255, 292, 333, 377, 425, 477, 533, 593, 658, 727, 801, 880, 964, 1053, 1147, 1247, 1352, 1463, 1580, 1703, 1832, 1968, 2110, 2259, 2415, 2578, 2748, 2925, 3110, 3302
Offset: 0

Views

Author

Mircea Merca, Dec 10 2010

Keywords

Comments

The round function is defined here by round(x) = floor(x + 1/2).

Examples

			a(13) = 0 + 0 + 0 + 1 + 1 + 2 + 3 + 4 + 5 + 6 + 8 + 9 + 11 + 13 = 63.
		

Crossrefs

Programs

  • Magma
    [Round(n*(n+1)*(2*n+1)/78): n in [0..60]]; // Vincenzo Librandi, Jun 23 2011
  • Maple
    seq(round(n*(n+1)*(2*n+1)/78),n=0..50)
  • PARI
    s=0;vector(90,n,s+=n^2\13)
    

Formula

a(n) = round(n*(n+1)*(2*n+1)/78).
a(n) = floor((n+3)*(2*n^2 - 3*n + 10)/78).
a(n) = ceiling((n-2)*(2*n^2 + 7*n + 15)/78).
a(n) = a(n-13) + (n+1)*(n-13) + 63, n > 12.
a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) + a(n-13) - 3*a(n-14) + 3*a(n-15) - a(n-16) with g.f. x^3*(1+x)*(x^2 - x + 1)*(x^6 - x^5 + x^4 - x^3 + x^2 - x + 1) / ( (x^12 + x^11 + x^10 + x^9 + x^8 + x^7 + x^6 + x^5 + x^4 + x^3 + x^2 + x + 1)*(x-1)^4 ). - R. J. Mathar, Dec 13 2010

A177189 Partial sums of round(n^2/16).

Original entry on oeis.org

0, 0, 0, 1, 2, 4, 6, 9, 13, 18, 24, 32, 41, 52, 64, 78, 94, 112, 132, 155, 180, 208, 238, 271, 307, 346, 388, 434, 483, 536, 592, 652, 716, 784, 856, 933, 1014, 1100, 1190, 1285, 1385, 1490, 1600, 1716, 1837, 1964, 2096, 2234, 2378, 2528, 2684
Offset: 0

Views

Author

Mircea Merca, Dec 10 2010

Keywords

Comments

The round function is defined here by round(x) = floor(x + 1/2).
There are several sequences of integers of the form round(n^2/k) for whose partial sums we can establish identities as following (only for k = 2, ..., 9, 11, 12, 13, 16, 17, 19, 20, 28, 29, 36, 44).

Examples

			a(16) = 0 + 0 + 0 + 1 + 1 + 2 + 2 + 3 + 4 + 5 + 6 + 8 + 9 + 11 + 12 + 14 + 16 = 94.
		

Crossrefs

Programs

  • Magma
    [Floor((n+3)*(2*n^2-3*n+13)/96): n in [0..50]]; // Vincenzo Librandi, Apr 29 2011
  • Maple
    seq(round((2*n^3+3*n^2+4*n)/96),n=0..50)
  • Mathematica
    Accumulate[Round[Range[0,50]^2/16]]  (* Harvey P. Dale, Mar 16 2011 *)

Formula

a(n) = round((2*n+1)*(2*n^2 + 2*n + 3)/192).
a(n) = floor((n+3)*(2*n^2 - 3*n + 13)/96).
a(n) = ceiling((n-2)*(2*n^2 + 7*n + 18)/96).
a(n) = round((2*n^3 + 3*n^2 + 4*n)/96).
a(n) = a(n-16) + (n+1)*(n-16) + 94, n > 15.
a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) + a(n-8) - 3*a(n-9) + 3*a(n-10) - a(n-11) with g.f. x^3*(1 - x + x^2 + x^4 - x^3) / ( (1+x)*(1+x^2)*(1+x^4)*(x-1)^4 ). - R. J. Mathar, Dec 13 2010

A177205 Partial sums of round(n^2/17).

Original entry on oeis.org

0, 0, 0, 1, 2, 3, 5, 8, 12, 17, 23, 30, 38, 48, 60, 73, 88, 105, 124, 145, 169, 195, 223, 254, 288, 325, 365, 408, 454, 503, 556, 613, 673, 737, 805, 877, 953, 1034, 1119, 1208, 1302, 1401, 1505, 1614, 1728, 1847, 1971, 2101, 2237, 2378, 2525
Offset: 0

Views

Author

Mircea Merca, Dec 10 2010

Keywords

Comments

The round function is defined here by round(x)=floor(x+1/2).
There are several sequences of integers of the form round(n^2/k) for whose partial sums we can establish identities as following (only for k = 2, ..., 9, 11, 12, 13, 16, 17, 19, 20, 28, 29, 36, 44).

Examples

			a(17) = 0 + 0 + 0 + 1 + 1 + 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 10 + 12 + 13 + 15 + 17 = 105.
		

Crossrefs

Programs

  • Magma
    [Floor((2*n^3+3*n^2+n+36)/102): n in [0..50]]; // Vincenzo Librandi, Apr 29 2011
  • Maple
    seq(round(n*(n+1)*(2*n+1)/102),n=0..50)
  • Mathematica
    Accumulate[Round[Range[0,50]^2/17]] (* Harvey P. Dale, Jul 04 2022 *)

Formula

a(n) = round(n*(n+1)*(2*n+1)/102).
a(n) = floor((2*n^3 + 3*n^2 + n + 36)/102).
a(n) = ceiling((2*n^3 + 3*n^2 + n - 36)/102).
a(n) = a(n-17) + (n+1)*(n-17) + 105, n > 16.
a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) + a(n-17) - 3*a(n-18) + 3*a(n-19) - a(n-20) with g.f. x^3 *(1+x) *(x^12 - 2*x^11 + 2*x^10 - x^9 + x^8 - x^7 + x^6 - x^5 + x^4 - x^3 + 2*x^2 - 2*x + 1) / ( (x^16 + x^15 + x^14 + x^13 + x^12 + x^11 + x^10 + x^9 + x^8 + x^7 + x^6 + x^5 + x^4 + x^3 + x^2 + x + 1) *(x-1)^4 ). - R. J. Mathar, Dec 13 2010

A177237 Partial sums of round(n^2/19).

Original entry on oeis.org

0, 0, 0, 0, 1, 2, 4, 7, 10, 14, 19, 25, 33, 42, 52, 64, 77, 92, 109, 128, 149, 172, 197, 225, 255, 288, 324, 362, 403, 447, 494, 545, 599, 656, 717, 781, 849, 921, 997, 1077, 1161, 1249, 1342, 1439, 1541, 1648, 1759, 1875, 1996, 2122, 2254
Offset: 0

Views

Author

Mircea Merca, Dec 10 2010

Keywords

Comments

The round function is defined here by round(x) = floor(x + 1/2).
There are several sequences of integers of the form round(n^2/k) for whose partial sums we can establish identities as following (only for k = 2, ..., 9, 11, 12, 13, 16, 17, 19, 20, 28, 29, 36, 44).

Examples

			a(19) = 0 + 0 + 0 + 0 + 1 + 1 + 2 + 3 + 3 + 4 + 5 + 6 + 8 + 9 + 10 + 12 + 13 + 15 + 17 + 19 = 128.
		

Crossrefs

Programs

  • Magma
    [Floor((2*n^3+3*n^2-11*n+42)/114): n in [0..50]]; // Vincenzo Librandi, Apr 29 2011
    
  • Maple
    seq(round((2*n^3+3*n^2-11*n)/114),n=0..50)
  • Mathematica
    Accumulate[Round[Range[0,50]^2/19]] (* Harvey P. Dale, Aug 15 2022 *)
  • SageMath
    [(2*n^3 +3*n^2 -11*n +42)//114 for n in range(61)] # G. C. Greubel, Apr 27 2024

Formula

a(n) = round((n-2)*(n+3)*(2*n+1)/114).
a(n) = floor((2*n^3 + 3*n^2 - 11*n + 42)/114).
a(n) = ceiling((2*n^3 + 3*n^2 - 11*n - 54)/114).
a(n) = round((2*n^3 + 3*n^2 - 11*n)/114).
a(n) = a(n-19) + (n+1)*(n-19) + 128, n > 18.
From R. J. Mathar, Dec 13 2010: (Start)
a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) + a(n-19) - 3*a(n-20) + 3*a(n-21) - a(n-22).
G.f.: x^4*(1+x)*(1 - x + x^2 - x^3 + x^4)*(1 - x + x^2 - x^4 + x^6 - x^7 + x^8)/((1-x)^3 * (1 - x^19)). (End)

A177239 Partial sums of round(n^2/20).

Original entry on oeis.org

0, 0, 0, 0, 1, 2, 4, 6, 9, 13, 18, 24, 31, 39, 49, 60, 73, 87, 103, 121, 141, 163, 187, 213, 242, 273, 307, 343, 382, 424, 469, 517, 568, 622, 680, 741, 806, 874, 946, 1022, 1102, 1186, 1274, 1366, 1463, 1564, 1670, 1780, 1895, 2015, 2140
Offset: 0

Views

Author

Mircea Merca, Dec 10 2010

Keywords

Comments

The round function is defined here by round(x) = floor(x + 1/2).
There are several sequences of integers of the form round(n^2/k) for whose partial sums we can establish identities as following (only for k = 2, ..., 9, 11, 12, 13, 16, 17, 19, 20, 28, 29, 36, 44).

Examples

			a(20) = 0 + 0 + 0 + 0 + 1 + 1 + 2 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 10 + 11 + 13 + 14 + 16 + 18 + 20 = 141.
		

Crossrefs

Programs

  • Magma
    [Floor((n+4)*(2*n^2-5*n+6)/120): n in [0..50]]; // Vincenzo Librandi, Apr 29 2011
    
  • Maple
    seq(round(n*(n-2)*(2*n+7)/120),n=0..50)
  • Mathematica
    f[n_] := Round[n^2/20]; Accumulate@ Array[f, 51, 0] (* Robert G. Wilson v, Dec 20 2010 *)
  • SageMath
    [(n+4)*(2*n^2 -5*n +6)//120 for n in range(56)] # G. C. Greubel, Apr 27 2024

Formula

a(n) = A001304(n-4).
a(n) = round((2*n+1)*(2*n^2 + 2*n - 15)/240).
a(n) = floor((n+4)*(2*n^2 - 5*n + 6)/120).
a(n) = ceiling((n-3)*(2*n^2 + 9*n + 13)120).
a(n) = round(n*(n-2)*(2*n+7)/120).
a(n) = a(n-20) + (n+1)*(n-20) + 141, n > 19.
From R. J. Mathar, Dec 12 2010: (Start)
a(n) = 2*a(n-1) - 2*a(n-3) + a(n-4) + a(n-5) - 2*a(n-6) + 2*a(n-8) - a(n-9).
G.f.: x^4 / ( (1+x)*(1+x+x^2+x^3+x^4)*(1-x)^4 ). (End)

A177277 Partial sums of round(n^2/28).

Original entry on oeis.org

0, 0, 0, 0, 1, 2, 3, 5, 7, 10, 14, 18, 23, 29, 36, 44, 53, 63, 75, 88, 102, 118, 135, 154, 175, 197, 221, 247, 275, 305, 337, 371, 408, 447, 488, 532, 578, 627, 679, 733, 790, 850, 913, 979, 1048, 1120, 1196, 1275, 1357, 1443, 1532
Offset: 0

Views

Author

Mircea Merca, Dec 10 2010

Keywords

Comments

The round function, also called the nearest integer function, is defined here by round(x) = floor(x + 1/2).
There are several sequences of integers of the form round(n^2/k) for whose partial sums we can establish identities as following (only for k = 2, ..., 9, 11, 12, 13, 16, 17, 19, 20, 28, 29, 36, 44).

Examples

			a(28) = 0 + 0 + 0 + 1 + 1 + 1 + 2 + 2 + 3 + 4 + 4 + 5 + 6 + 7 + 8 + 9 + 10 + 12 + 13 + 14 + 16 + 17 + 19 + 21 + 22 + 24 + 26 + 28 = 275.
		

Crossrefs

Programs

  • Magma
    [Floor((n+4)*(2*n^2-5*n+18)/168): n in [0..50]]; // Vincenzo Librandi, Apr 29 2011
  • Maple
    seq(round(n*(n+2)*(2*n-1)/168),n=0..50)
  • Mathematica
    Accumulate[Floor[Range[0,50]^2/28+1/2]] (* Harvey P. Dale, Feb 02 2012 *)

Formula

a(n) = round((2*n+1)*(2*n^2 + 2*n - 3)/336).
a(n) = floor((n+4)*(2*n^2 - 5*n + 18)/168).
a(n) = ceiling((n-3)*(2*n^2 + 9*n + 25)/168).
a(n) = round(n*(n+2)*(2*n-1)/168).
a(n) = a(n-28) + (n+1)*(n-28) + 275, n > 27.
a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) + a(n-14) - 3*a(n-15) + 3*a(n-16) - a(n-17) with g.f. x^4*(1 - x + x^3 - x^4 + x^5 - x^7 + x^8) / ( (1+x)*(x^6 + x^5 + x^4 + x^3 + x^2 + x + 1)*(x^6 - x^5 + x^4 - x^3 + x^2 - x + 1)*(x-1)^4 ). - R. J. Mathar, Dec 12 2010

A177332 Partial sums of round(n^2/29).

Original entry on oeis.org

0, 0, 0, 0, 1, 2, 3, 5, 7, 10, 13, 17, 22, 28, 35, 43, 52, 62, 73, 85, 99, 114, 131, 149, 169, 191, 214, 239, 266, 295, 326, 359, 394, 432, 472, 514, 559, 606, 656, 708, 763, 821, 882, 946, 1013, 1083, 1156, 1232, 1311, 1394, 1480
Offset: 0

Views

Author

Mircea Merca, Dec 10 2010

Keywords

Comments

The round function is defined here by round(x) = floor(x + 1/2).
There are several sequences of integers of the form round(n^2/k) for whose partial sums we can establish identities as following (only for k = 2, ..., 9, 11, 12, 13, 16, 17, 19, 20, 28, 29, 36, 44).

Examples

			a(17) = 0 + 0 + 0 + 0 + 1 + 1 + 1 + 2 + 2 + 3 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 = 62.
		

Crossrefs

Programs

  • Magma
    [Floor((n+4)*(2*n^2-5*n+21)/174): n in [0..50]]; // Vincenzo Librandi, Apr 29 2011
    
  • Maple
    seq(round(n*(n+1)*(2*n+1)/174),n=0..50)
  • Mathematica
    Accumulate[Table[Round[n^2/29],{n,0,60}]] (* Harvey P. Dale, Dec 18 2010 *)
  • PARI
    a(n)=(2*n^3+3*n^2+n+84)\174 \\ Charles R Greathouse IV, Apr 06 2012
    
  • Python
    def A177332(n): return (n*(n*(2*n + 3) + 1) + 84)//174 # Chai Wah Wu, Jan 31 2023

Formula

a(n) = round(n*(n+1)*(2*n+1)/174).
a(n) = floor((n+4)*(2*n^2 - 5*n + 21)/174).
a(n) = ceiling((n-3)*(2*n^2 + 9*n + 28)/174).
a(n) = a(n-29) + (n+1)*(n-29) + 266, n > 28.
a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) + a(n-29) - 3*a(n-30) + 3*a(n-31) - a(n-32). - R. J. Mathar, Dec 13 2010
G.f.: x^4*(x+1)*(x^2 - x + 1)*(x^4 - x^2 + 1)*(x^6 - x^5 + x^4 - x^3 + x^2 - x + 1)*(x^10 - x^6 + x^5 - x^4 + 1)/((x-1)^4*(x^28 + x^27 + x^26 + x^25 + x^24 + x^23 + x^22 + x^21 + x^20 + x^19 + x^18 + x^17 + x^16 + x^15 + x^14 + x^13 + x^12 + x^11 + x^10 + x^9 + x^8 + x^7 + x^6 + x^5 + x^4 + x^3 + x^2 + x + 1)). - Colin Barker, Apr 06 2012

A177337 Partial sums of round(n^2/36).

Original entry on oeis.org

0, 0, 0, 0, 0, 1, 2, 3, 5, 7, 10, 13, 17, 22, 27, 33, 40, 48, 57, 67, 78, 90, 103, 118, 134, 151, 170, 190, 212, 235, 260, 287, 315, 345, 377, 411, 447, 485, 525, 567, 611, 658, 707, 758, 812, 868, 927, 988, 1052, 1119, 1188
Offset: 0

Views

Author

Mircea Merca, Dec 10 2010

Keywords

Comments

The round function is defined here by round(x) = floor(x + 1/2).

Examples

			a(19) = 0 + 0 + 0 + 0 + 0 + 1 + 1 + 1 + 2 + 2 + 3 + 3 + 4 + 5 + 5 + 6 + 7 + 8 + 9 + 10 = 67.
		

Crossrefs

Programs

  • Magma
    [Floor((n+5)*(2*n^2-7*n+17)/216): n in [0..50]]; // Vincenzo Librandi, Apr 29 2011
  • Maple
    seq(round((2*n^3+3*n^2-18*n)/216),n=0..50)
  • Mathematica
    Accumulate[Floor[Range[0,60]^2/36+1/2]] (* Harvey P. Dale, Sep 29 2011 *)

Formula

a(n) = round((2*n+1)*(2*n^2 + 2*n - 19)/432).
a(n) = floor((n+5)*(2*n^2 - 7*n + 17)/216).
a(n) = ceiling((n-4)*(2*n^2 + 11*n + 26)/216).
a(n) = round((2*n^3 + 3*n^2 - 18*n)/216).
a(n) = a(n-36) + (n+1)*(n-36) + 447, n > 35.
a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) + a(n-18) - 3*a(n-19) + 3*a(n-20) - a(n-21) with g.f. x^5*(1 - x + x^3 - x^4 + x^5 - x^6 + x^7 - x^9 + x^10) / ( (1+x) *(1 + x + x^2) *(x^2 - x + 1) *(x^6 + x^3 + 1) *(x^6 - x^3 + 1) *(x-1)^4 ). - R. J. Mathar, Dec 13 2010

A177339 Partial sums of round(n^2/44).

Original entry on oeis.org

0, 0, 0, 0, 0, 1, 2, 3, 4, 6, 8, 11, 14, 18, 22, 27, 33, 40, 47, 55, 64, 74, 85, 97, 110, 124, 139, 156, 174, 193, 213, 235, 258, 283, 309, 337, 366, 397, 430, 465, 501, 539, 579, 621, 665, 711, 759, 809, 861, 916, 973
Offset: 0

Views

Author

Mircea Merca, Dec 10 2010

Keywords

Comments

The round function is defined here by round(x) = floor(x + 1/2).
There are several sequences of integers of the form round(n^2/k) for whose partial sums we can establish identities as following (only for k = 2, ..., 9, 11, 12, 13, 16, 17, 19, 20, 28, 29, 36, 44).

Examples

			a(15) = 0 + 0 + 0 + 0 + 0 + 1 + 1 + 1 + 1 + 2 + 2 + 3 + 3 + 4 + 4 + 5 = 27.
		

Crossrefs

Programs

  • Magma
    [Round((2*n+1)*(2*n^2+2*n-15)/528): n in [0..60]]; // Vincenzo Librandi, Jun 23 2011
  • Maple
    seq(round(n*(n-2)*(2*n+7)/264),n=0..50)

Formula

a(n) = round((2*n+1)*(2*n^2 + 2*n - 15)/528).
a(n) = floor((n+5)*(2*n^2 - 7*n + 21)/264).
a(n) = ceiling((n-4)*(2*n^2 + 11*n + 30)/264).
a(n) = round(n*(n-2)*(2*n+7)/264).
a(n) = a(n-44) + (n+1)*(n-44) + 665, n > 43.
a(n) = 2*a(n-1) - 2*a(n-3) + a(n-4) + a(n-11) - 2*a(n-12) + 2*a(n-14) - a(n-15) with g.f. x^5*(1 - x^2 + x^4) / ( (1+x) *(x^10 + x^9 + x^8 + x^7 + x^6 + x^5 + x^4 + x^3 + x^2 + x + 1) *(x-1)^4 ). - R. J. Mathar, Dec 13 2010
Showing 1-10 of 10 results.