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.

A083064 Square number array T(n,k) = (k*(k+2)^n+1)/(k+1) read by antidiagonals.

Original entry on oeis.org

1, 1, 1, 1, 2, 1, 1, 3, 5, 1, 1, 4, 11, 14, 1, 1, 5, 19, 43, 41, 1, 1, 6, 29, 94, 171, 122, 1, 1, 7, 41, 173, 469, 683, 365, 1, 1, 8, 55, 286, 1037, 2344, 2731, 1094, 1, 1, 9, 71, 439, 2001, 6221, 11719, 10923, 3281, 1, 1, 10, 89, 638, 3511, 14006, 37325, 58594, 43691, 9842, 1
Offset: 0

Views

Author

Paul Barry, Apr 21 2003

Keywords

Examples

			Rows begin:
1  1   1    1     1      1       1        1         1 ...
1  2   5   14    41    122     365     1094      3281 ...  A007051
1  3  11   43   171    683    2731    10923     43691 ...  A007583
1  4  19   94   469   2344   11719    58594    292969 ...  A083065
1  5  29  173  1037   6221   37325   223949   1343693 ...  A083066
1  6  41  286  2001  14006   98041   686286   4804001 ...  A083067
1  7  55  439  3511  28087  224695  1797559  14380471 ...  A083068
1  8  71  638  5741  51668  465011  4185098  37665881 ...  A187709
1  9  89  889  8889  88889  888889  8888889  88888889 ...  A059482
1 10 109 1198 13177 144946 1594405 17538454 192922993 ...  A199760, etc.
Column 2: A000027;
column 3: A028387;
column 4: A083074;
column 5: A125082;
column 6: A125083.
Diagonals:
1,  2,  11,   94,  1037,  14006, ... A083069;
1,  3,  19,  173,  2001,  28087, ... A083071;
1,  4,  29,  286,  3511,  51668, ... A083072;
1,  5,  41,  439,  5741,  88889, ... A083073;
1,  5,  43,  469,  6221,  98041, ... A083070;
1, 14, 171, 2344, 37325, 686286, ... A191690.
Triangle begins:
1;
1, 1;
1, 2, 1;
1, 3, 5, 1;
1, 4, 11, 14, 1;
1, 5, 19, 43, 41, 1;
1, 6, 29, 94, 171, 122, 1; etc.
		

Crossrefs

Extensions

Edited by Bruno Berselli, Jun 21 2013

A083071 First subdiagonal of number array A083064.

Original entry on oeis.org

1, 3, 19, 173, 2001, 28087, 465011, 8888889, 192922993, 4690709411, 126370284195, 3738060156613, 120478742327009, 4203359652212463, 157854212399438371, 6349779403743490289, 272416890591642213921, 12417347368421052631579
Offset: 0

Views

Author

Paul Barry, Apr 21 2003

Keywords

Crossrefs

Formula

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

A083070 First superdiagonal of number array A083064.

Original entry on oeis.org

1, 5, 43, 469, 6221, 98041, 1797559, 37665881, 888888889, 23343682141, 675462155171, 21356578028941, 732659790696133, 27107717023577009, 1076060070966390511, 45619867383437689201, 2057328526812890853617
Offset: 1

Views

Author

Paul Barry, Apr 21 2003

Keywords

Crossrefs

Formula

a(n) = ((n-1)*(n+1)^n + 1)/n.

A125598 a(n) = ((n+1)^(n-1) - 1)/n.

Original entry on oeis.org

0, 1, 5, 31, 259, 2801, 37449, 597871, 11111111, 235794769, 5628851293, 149346699503, 4361070182715, 139013933454241, 4803839602528529, 178901440719363487, 7143501829211426575, 304465936543600121441
Offset: 1

Views

Author

Alexander Adamchuk, Nov 26 2006

Keywords

Comments

Odd prime p divides a(p-2).
a(n) is prime for n = {3,4,6,74, ...}; prime terms are {5, 31, 2801, ...}.
a(n) is the (n-1)-th generalized repunit in base (n+1). For example, a(5) = 259 which is 1111 in base 6. - Mathew Englander, Oct 20 2020

Crossrefs

Cf. A000272 (n^(n-2)), A125599.
Cf. other sequences of generalized repunits, such as A125118, A053696, A055129, A060072, A031973, A173468, A023037, A119598, A085104, and A162861.

Programs

  • Magma
    [((n+1)^(n-1) -1)/n: n in [1..25]]; // G. C. Greubel, Aug 15 2022
  • Mathematica
    Table[((n+1)^(n-1)-1)/n, {n,25}]
  • Sage
    [gaussian_binomial(n,1,n+2) for n in range(0,18)] # Zerinvary Lajos, May 31 2009
    

Formula

a(n) = ((n+1)^(n-1) - 1)/n.
a(n) = (A000272(n+1) - 1)/n.
a(2k-1)/(2k+1) = A125599(k) for k>0.
From Mathew Englander, Dec 17 2020: (Start)
a(n) = (A060072(n+1) - A083069(n-1))/2.
For n > 1, a(n) = Sum_{k=0..n-2} (n+1)^k.
For n > 1, a(n) = Sum_{j=0..n-2} n^j*C(n-1,j+1). (End)

A083072 A subdiagonal of number array A083064.

Original entry on oeis.org

1, 4, 29, 286, 3511, 51668, 888889, 17538454, 390892451, 9720791092, 267004296901, 8031916155134, 262709978263279, 9285541905849316, 352765522430193905, 14337731083770642838, 620867368421052631579
Offset: 0

Views

Author

Paul Barry, Apr 21 2003

Keywords

Crossrefs

Formula

a(n) = ((n+2)*(n+4)^n + 1)/(n+3).

A083073 A subdiagonal of number array A083064.

Original entry on oeis.org

1, 5, 41, 439, 5741, 88889, 1594405, 32574371, 747753161, 19071735493, 535461077009, 16419373641455, 546208347402901, 19598084579455217, 754617425461612781, 31043368421052631579, 1359040255729886061905
Offset: 0

Views

Author

Paul Barry, Apr 21 2003

Keywords

Crossrefs

Formula

a(n) = ((n+3)*(n+5)^n + 1)/(n+4).
Showing 1-6 of 6 results.