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.

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A163282 Triangle read by rows in which row n lists n+1 terms, starting with n^2 and ending with n^3, such that difference between successive terms is equal to n^2 - n.

Original entry on oeis.org

0, 1, 1, 4, 6, 8, 9, 15, 21, 27, 16, 28, 40, 52, 64, 25, 45, 65, 85, 105, 125, 36, 66, 96, 126, 156, 186, 216, 49, 91, 133, 175, 217, 259, 301, 343, 64, 120, 176, 232, 288, 344, 400, 456, 512, 81, 153, 225, 297, 369, 441, 513, 585, 657, 729, 100, 190, 280, 370, 460, 550
Offset: 0

Views

Author

Omar E. Pol, Jul 24 2009

Keywords

Comments

The first term of row n is A000290(n) and the last term of row n is A000578(n).

Examples

			Triangle begins:
    0;
    1,   1;
    4,   6,   8;
    9,  15,  21,  27;
   16,  28,  40,  52,  64;
   25,  45,  65,  85, 105, 125;
   36,  66,  96, 126, 156, 186, 216;
   49,  91, 133, 175, 217, 259, 301, 343;
   64, 120, 176, 232, 288, 344, 400, 456, 512;
   81, 153, 225, 297, 369, 441, 513, 585, 657, 729;
  100, 190, 280, 370, 460, 550, 640, 730, 820, 910, 1000;
		

Crossrefs

Programs

  • Magma
    /* As triangle: */ [[n^2+k*(n^2-n): k in [0..n]]: n in [0.. 15]]; // Vincenzo Librandi, Dec 13 2016
  • Mathematica
    T[n_, k_] := n^2 + k*(n^2 - n); Table[T[n, k], {n,0,10}, {k,0,n}] //Flatten (* G. C. Greubel, Dec 13 2016 *)
    Join[{0,1},Table[Range[n^2,n^3,n^2-n],{n,10}]]//Flatten (* Harvey P. Dale, Sep 09 2019 *)
  • PARI
    A163282(n,k)=n^2+k*(n^2-n) \\ Michael B. Porter, Feb 25 2010
    

Formula

T(n, k) = n^2 + k*(n^2 - n), for 0 <= k <= n, n>= 0. - G. C. Greubel, Dec 13 2016

A163284 Triangle read by rows in which row n lists n+1 terms, starting with n^4 and ending with n^5, such that the difference between successive terms is equal to n^4 - n^3.

Original entry on oeis.org

0, 1, 1, 16, 24, 32, 81, 135, 189, 243, 256, 448, 640, 832, 1024, 625, 1125, 1625, 2125, 2625, 3125, 1296, 2376, 3456, 4536, 5616, 6696, 7776, 2401, 4459, 6517, 8575, 10633, 12691, 14749, 16807, 4096, 7680, 11264, 14848, 18432, 22016, 25600, 29184, 32768
Offset: 0

Views

Author

Omar E. Pol, Jul 24 2009

Keywords

Comments

The first term of row n is A000583(n) and the last term of row n is A000584(n).

Examples

			Triangle begins:
0;
1,1;
16,24,32;
81,135,189,243;
256,448,640,832,1024;
625,1125,1625,2125,2625,3125;
1296,2376,3456,4536,5616,6696,7776;
2401,4459,6517,8575,10633,12691,14749,16807;
4096,7680,11264,14848,18432,22016,25600,29184,32768;
6561,12393,18225,24057,29889,35721,41553,47385,53217,59049;
10000,19000,28000,37000,46000,55000,64000,73000,82000,91000,100000;
		

Crossrefs

Programs

  • Mathematica
    Table[n^4 + k*(n^4 - n^3), {n,0,15}, {k,0,n}] // Flatten (* G. C. Greubel, Dec 17 2016 *)
  • PARI
    A163284(n, k)=n^4 +k*(n^4 -n^3) \\ G. C. Greubel, Dec 17 2016

A163285 Triangle read by rows in which row n lists n+1 terms, starting with n^5 and ending with n^6, such that the difference between successive terms is equal to n^5 - n^4.

Original entry on oeis.org

0, 1, 1, 32, 48, 64, 243, 405, 567, 729, 1024, 1792, 2560, 3328, 4096, 3125, 5625, 8125, 10625, 13125, 15625, 7776, 14256, 20736, 27216, 33696, 40176, 46656, 16807, 31213, 45619, 60025, 74431, 88837, 103243, 117649, 32768, 61440, 90112, 118784, 147456
Offset: 0

Views

Author

Omar E. Pol, Jul 24 2009

Keywords

Comments

The first term of row n is A000584(n) and the last term of row n is A001014(n).
The main entry for this sequence is A159797. See also A163282, A163283 and A163284.
Row sums give A163275. - Omar E. Pol, Mar 18 2012

Examples

			Triangle begins:
0;
1,1;
32,48,64;
243,405,567,729;
1024,1792,2560,3328,4096;
3125,5625,8125,10625,13125,15625;
7776,14256,20736,27216,33696,40176,46656;
16807,31213,45619,60025,74431,88837,103243,117649;
32768,61440,90112,118784,147456,176128,204800,233472,262144;
59049,111537,164025,216513,269001,321489,373977,426465,478953,531441;
100000,190000,280000,370000,460000,550000,640000,730000,820000,910000,1000000;
		

Crossrefs

Programs

  • Mathematica
    rw[n_]:=Range[n^5,n^6,n^5-n^4]; Join[{0,1},Flatten[Array[rw,10]]] (* Harvey P. Dale, Mar 18 2012 *)
  • PARI
    A163285(n, k)=n^5 +k*(n^5 -n^4) \\ G. C. Greubel, Dec 17 2016

A162608 Triangle read by rows in which row n lists n+1 terms, starting with n!, such that the difference between successive terms is also equal to n!.

Original entry on oeis.org

1, 1, 2, 2, 4, 6, 6, 12, 18, 24, 24, 48, 72, 96, 120, 120, 240, 360, 480, 600, 720, 720, 1440, 2160, 2880, 3600, 4320, 5040, 5040, 10080, 15120, 20160, 25200, 30240, 35280, 40320, 40320, 80640, 120960, 161280, 201600, 241920, 282240, 322560, 362880
Offset: 0

Views

Author

Omar E. Pol, Jul 22 2009

Keywords

Comments

Note that the last term of the n-th row is the factorial of (n+1) = (n+1)! = A000142(n+1).
Sequence A178883 (with shape A000041) is a "refinement" of Table A162608; as expected, both sequences have row sums A001710(n+2). - Alford Arnold, Sep 28 2010
From Dennis P. Walsh, May 18 2020: (Start)
T(n,k) provides the number of length (n+2) permutations with elements 1 and 2 as cycle-mates in a (k+1)-cycle. We note that 1 and 2 are cycle-mates if they are elements of the same cycle in the permutation.
For example, T(3,2) counts the 12 permutations of length 5 that have 1 and 2 in the same 3 cycle, namely, (1 2 3)(4)(5), (1 3 2)(4)(5), (1 2 3)(4 5), (1 3 2)(4 5), (1 2 4)(3)(5), (1 4 2)(3)(5), (1 2 4)(3 5), (1 4 2)(3 5),(1 2 5)(3)(4), (1 5 2)(3)(4), (1 2 5)(3 4), and (1 5 2)(3 4).
Note that there are binomial(n,k-1) ways to choose the other (k-1) cycle-mates of 1 and 2 in the (k+1)-cycle and then k! different (k+1)-cycles with these elements. Since there are (n+1-k)! ways to permute the remaining elements, we obtain T(n,k) = (n+1-k)!*k!*binomial(n,k-1) = n!*k. (End)

Examples

			Triangle begins:
1;
1,     2;
2,     4,     6;
6,     12,    18,     24;
24,    48,    72,     96,     120;
120,   240,   360,    480,    600,    720;
720,   1440,  2160,   2880,   3600,   4320,   5040;
5040,  10080, 15120,  20160,  25200,  30240,  35280,  40320;
40320, 80640, 120960, 161280, 201600, 241920, 282240, 322560, 362880;
362880,725760,1088640,1451520,1814400,2177280,2540160,2903040,3265920,3628800;
...
Observation: It appears that rows sums = A001710(n+2).
		

Crossrefs

Programs

  • Haskell
    a162608 n k = a162608_tabl !! n !! k
    a162608_row n = a162608_tabl !! n
    a162608_tabl = map fst $ iterate f ([1], 1) where
       f (row, n) = (row' ++ [head row' + last row'], n + 1) where
         row' = map (* n) row
    -- Reinhard Zumkeller, Mar 09 2012
    
  • Magma
    /* As triangle */ [[Factorial(n)*k: k in [1..n+1]]: n in [0.. 15]]; // Vincenzo Librandi, Jul 04 2015
  • Mathematica
    Table[k n!, {n, 0, 8}, {k, n + 1}] // Flatten (* Michael De Vlieger, Jul 03 2015 *)

Formula

From Robert Israel, Jul 03 2015: (Start)
T(n,k) = n!*k, k = 1 .. n+1.
T(n+1,k) = (n+1)*T(n,k).
T(n,k+1) = T(n,k)+T(n,1). (End)

A162623 Triangle read by rows in which row n lists n terms, starting with n, such that the difference between successive terms is equal to n^4 - 1 = A123865(n).

Original entry on oeis.org

1, 2, 17, 3, 83, 163, 4, 259, 514, 769, 5, 629, 1253, 1877, 2501, 6, 1301, 2596, 3891, 5186, 6481, 7, 2407, 4807, 7207, 9607, 12007, 14407, 8, 4103, 8198, 12293, 16388, 20483, 24578, 28673, 9, 6569, 13129, 19689, 26249, 32809, 39369, 45929, 52489, 10
Offset: 1

Views

Author

Omar E. Pol, Jul 12 2009

Keywords

Comments

See also the triangles of A162622 and A162624.

Examples

			Triangle begins:
  1;
  2,   17;
  3,   83,  163;
  4,  259,  514,  769;
  5,  629, 1253, 1877, 2501;
  6, 1301, 2596, 3891, 5186, 6481;
		

Crossrefs

Programs

  • Maple
    A162623 := proc(n,k) n+k*(n^4-1) ; end: seq(seq(A162623(n,k),k=0..n-1),n=1..15) ; # R. J. Mathar, Sep 27 2009
  • Mathematica
    dst[n_]:=Module[{c=n^4-1},Range[n,n*c,c]]; Flatten[Join[{1},Table[dst[n],{n,2,10}]]] (* Harvey P. Dale, Jul 29 2014 *)

Formula

Row sums: n*(n^5 - n^4 + n + 1)/2. - R. J. Mathar, Jul 20 2009

Extensions

More terms from R. J. Mathar, Sep 27 2009

A163283 Triangle read by rows in which row n lists n+1 terms, starting with n^3 and ending with n^4, such that the difference between successive terms is equal to n^3 - n^2.

Original entry on oeis.org

0, 1, 1, 8, 12, 16, 27, 45, 63, 81, 64, 112, 160, 208, 256, 125, 225, 325, 425, 525, 625, 216, 396, 576, 756, 936, 1116, 1296, 343, 637, 931, 1225, 1519, 1813, 2107, 2401, 512, 960, 1408, 1856, 2304, 2752, 3200, 3648, 4096, 729, 1377, 2025, 2673, 3321, 3969
Offset: 0

Views

Author

Omar E. Pol, Jul 24 2009

Keywords

Comments

The first term of row n is A000578(n) and the last term of row n is A000583(n).

Examples

			Triangle begins:
0;
1,    1;
8,    12,   16;
27,   45,   63,   81;
64,   112,  160,  208,  256;
125,  225,  325,  425,  525,  625;
216,  396,  576,  756,  936,  1116, 1296;
343,  637,  931,  1225, 1519, 1813, 2107, 2401;
512,  960,  1408, 1856, 2304, 2752, 3200, 3648, 4096;
729,  1377, 2025, 2673, 3321, 3969, 4617, 5265, 5913, 6561;
1000, 1900, 2800, 3700, 4600, 5500, 6400, 7300, 8200, 9100, 10000;
...
		

Crossrefs

Programs

  • Mathematica
    Table[n^3 + k*(n^3 - n^2), {n, 0, 5}, {k, 0, n}]//Flatten (* G. C. Greubel, Dec 13 2016 *)
  • PARI
    A163283(n, k)=n^3 +k*(n^3 -n^2) \\ G. C. Greubel, Dec 13 2016

Formula

T(n, k) = n^3 + k*(n^3 - n^2), for 0 <= k <= n, n >= 0. - G. C. Greubel, Dec 13 2016

Extensions

Edited by Omar E. Pol, Jul 25 2009

A162619 Triangle read by rows in which row n lists n consecutive natural numbers A000027, starting with A014689(n) = A000040(n)-n.

Original entry on oeis.org

1, 1, 2, 2, 3, 4, 3, 4, 5, 6, 6, 7, 8, 9, 10, 7, 8, 9, 10, 11, 12, 10, 11, 12, 13, 14, 15, 16, 11, 12, 13, 14, 15, 16, 17, 18, 14, 15, 16, 17, 18, 19, 20, 21, 22, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 25, 26, 27, 28, 29, 30, 31, 32, 33
Offset: 1

Views

Author

Omar E. Pol, Jul 10 2009

Keywords

Comments

Note that the last term of the n-th row is A000040(n)-1 = A006093(n).
See also A162618 and A162620.

Examples

			Triangle begins:
.1;
.1, 2;
.2, 3, 4;
.3, 4, 5, 6;
.6, 7, 8, 9,10;
.7, 8, 9,10,11,12;
10,11,12,13,14,15,16;
11,12,13,14,15,16,17,18;
14,15,16,17,18,19,20,21,22;
19,20,21,22,23,24,25,26,27,28;
20,21,22,23,24,25,26,27,28,29,30;
		

Crossrefs

A162618 Triangle read by rows in which row n lists n consecutive natural numbers A000027, starting with A008578(n-1) - n + 1.

Original entry on oeis.org

1, 1, 2, 1, 2, 3, 2, 3, 4, 5, 3, 4, 5, 6, 7, 6, 7, 8, 9, 10, 11, 7, 8, 9, 10, 11, 12, 13, 10, 11, 12, 13, 14, 15, 16, 17, 11, 12, 13, 14, 15, 16, 17, 18, 19, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30
Offset: 1

Views

Author

Omar E. Pol, Jul 10 2009

Keywords

Comments

Note that the last term of the n-th row is the noncomposite number A008578(n-1).

Examples

			Contribution from _Omar E. Pol_, Jul 15 2009: (Start)
Triangle begins:
   1;
   1,  2;
   1,  2,  3;
   2,  3,  4,  5;
   3,  4,  5,  6,  7;
   6,  7,  8,  9, 10, 11;
   7,  8,  9, 10, 11, 12, 13;
  10, 11, 12, 13, 14, 15, 16, 17;
  11, 12, 13, 14, 15, 16, 17, 18, 19;
  14, 15, 16, 17, 18, 19, 20, 21, 22, 23;
  19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29;
  20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31;
(End)
		

Crossrefs

A162620 Triangle read by rows in which row n lists n consecutive natural numbers A000027, starting with A000040(n)-n+1.

Original entry on oeis.org

2, 2, 3, 3, 4, 5, 4, 5, 6, 7, 7, 8, 9, 10, 11, 8, 9, 10, 11, 12, 13, 11, 12, 13, 14, 15, 16, 17, 12, 13, 14, 15, 16, 17, 18, 19, 15, 16, 17, 18, 19, 20, 21, 22, 23, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 26, 27, 28, 29, 30, 31, 32, 33
Offset: 1

Views

Author

Omar E. Pol, Jul 10 2009

Keywords

Comments

Note that the last term of the n-th row is the n-th prime A000040(n).
See also A162618 and A162619.

Examples

			Triangle begins:
.2;
.2, 3;
.3, 4, 5;
.4, 5, 6, 7;
.7, 8, 9,10,11;
.8, 9,10,11,12,13;
11,12,13,14,15,16,17;
12,13,14,15,16,17,18,19;
15,16,17,18,19,20,21,22,23;
20,21,22,23,24,25,26,27,28,29;
21,22,23,24,25,26,27,28,29,30,31;
		

Crossrefs

A177058 a(n) = n^3 - 3n^2 + 3.

Original entry on oeis.org

3, 1, -1, 3, 19, 53, 111, 199, 323, 489, 703, 971, 1299, 1693, 2159, 2703, 3331, 4049, 4863, 5779, 6803, 7941, 9199, 10583, 12099, 13753, 15551, 17499, 19603, 21869, 24303, 26911, 29699, 32673, 35839, 39203, 42771, 46549, 50543, 54759, 59203
Offset: 0

Views

Author

Vincenzo Librandi, May 27 2010

Keywords

Comments

For n>2, fourth diagonal of A162611.

Crossrefs

Programs

  • Mathematica
    Table[n^3-3n^2+3,{n,0,40}] (* or *) LinearRecurrence[{4,-6,4,-1},{3,1,-1,3},50] (* Harvey P. Dale, May 15 2020 *)
  • PARI
    a(n)=n^3-3*n^2+3 \\ Charles R Greathouse IV, Jan 11 2012

Formula

From Bruno Berselli, Jun 04 2010: (Start)
G.f.: (3-11*x+13*x^2+x^3)/(1-x)^4.
a(n)-4*a(n-1)+6*a(n-2)-4*a(n-3)+a(n-4) = 0, with n>3.
a(n)+a(n-1) = 2*A081438(n-3), with n>2. (End)
G.f.: 3+x+x^2*G(0) where G(k) = 1 - x*(k+1)*(k+1)*(k+4)/(1 - 1/(1 - (k+1)*(k+1)*(k+4)/G(k+1))); (continued fraction, 3-step). - Sergei N. Gladkovskii, Oct 16 2012
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