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 1-3 of 3 results.

A276616 Square array A(n,k) = A276953(n,k)/n!, read by descending antidiagonals as A(1,1), A(1,2), A(2,1), A(1,3), A(2,2), A(3,1), etc.

Original entry on oeis.org

1, 3, 1, 4, 4, 1, 5, 6, 5, 1, 7, 7, 8, 6, 1, 9, 13, 9, 10, 7, 1, 10, 16, 21, 11, 12, 8, 1, 11, 18, 25, 31, 13, 14, 9, 1, 13, 19, 28, 36, 43, 15, 16, 10, 1, 15, 25, 29, 40, 49, 57, 17, 18, 11, 1, 16, 28, 41, 41, 54, 64, 73, 19, 20, 12, 1, 17, 30, 45, 61, 55, 70, 81, 91, 21, 22, 13, 1, 18, 31, 48, 66, 85, 71, 88, 100, 111, 23, 24, 14, 1
Offset: 1

Views

Author

Antti Karttunen, Sep 22 2016

Keywords

Examples

			The top left corner of the array:
  1, 3,  4,  5,  7,  9, 10, 11,  13,  15,  16,  17,  18,  19,  20,  21,  22
  1, 4,  6,  7, 13, 16, 18, 19,  25,  28,  30,  31,  36,  37,  39,  40,  42
  1, 5,  8,  9, 21, 25, 28, 29,  41,  45,  48,  49,  60,  61,  64,  65,  68
  1, 6, 10, 11, 31, 36, 40, 41,  61,  66,  70,  71,  90,  91,  95,  96, 100
  1, 7, 12, 13, 43, 49, 54, 55,  85,  91,  96,  97, 126, 127, 132, 133, 138
  1, 8, 14, 15, 57, 64, 70, 71, 113, 120, 126, 127, 168, 169, 175, 176, 182

Links

Crossrefs

Transpose: A276617.
Cf. A000142, A276953.
Row 1: A273670, row 2: A276931, row 3: A276934.
For columns, see the rows of transpose A276617.

Programs

Formula

A(n,k) = A276953(n,k)/n!

A276617 Square array A(n,k) = A276955(n,k)/k!, read by descending antidiagonals as A(1,1), A(1,2), A(2,1), A(1,3), A(2,2), A(3,1), etc.

Original entry on oeis.org

1, 1, 3, 1, 4, 4, 1, 5, 6, 5, 1, 6, 8, 7, 7, 1, 7, 10, 9, 13, 9, 1, 8, 12, 11, 21, 16, 10, 1, 9, 14, 13, 31, 25, 18, 11, 1, 10, 16, 15, 43, 36, 28, 19, 13, 1, 11, 18, 17, 57, 49, 40, 29, 25, 15, 1, 12, 20, 19, 73, 64, 54, 41, 41, 28, 16, 1, 13, 22, 21, 91, 81, 70, 55, 61, 45, 30, 17, 1, 14, 24, 23, 111, 100, 88, 71, 85, 66, 48, 31, 18
Offset: 1

Views

Author

Antti Karttunen, Sep 22 2016

Keywords

Examples

			The top left corner of the array:
1,  1,  1,  1,  1,  1,  1,   1,   1,   1,   1,   1,   1,   1,   1,   1,   1
3,  4,  5,  6,  7,  8,  9,  10,  11,  12,  13,  14,  15,  16,  17,  18,  19
4,  6,  8, 10, 12, 14, 16,  18,  20,  22,  24,  26,  28,  30,  32,  34,  36
5,  7,  9, 11, 13, 15, 17,  19,  21,  23,  25,  27,  29,  31,  33,  35,  37
7, 13, 21, 31, 43, 57, 73,  91, 111, 133, 157, 183, 211, 241, 273, 307, 343
9, 16, 25, 36, 49, 64, 81, 100, 121, 144, 169, 196, 225, 256, 289, 324, 361

Links

Crossrefs

Transpose: A276616.
Cf. A000142, A276955.
Columns 1-3: A273670, A276931, A276934.
Row 1: A000012, Row 2: n+2, Row 3: 2n+2, Row 4: 2n+3 (for n >= 1).
Row 5: A002061 (from a(3)=7 onward).
Row 6: squares (A000290, from a(3)=9 onward).
Row 7: A028552 (from a(2)=10 onward).
Row 8: A028387 (from a(2)=11 onward).

Programs

Formula

A(n,k) = A276955(n,k)/k!

A276932 Row 2 of A276953: a(n) = A153880(A273670(n)).

Original entry on oeis.org

2, 8, 12, 14, 26, 32, 36, 38, 50, 56, 60, 62, 72, 74, 78, 80, 84, 86, 122, 128, 132, 134, 146, 152, 156, 158, 170, 176, 180, 182, 192, 194, 198, 200, 204, 206, 242, 248, 252, 254, 266, 272, 276, 278, 290, 296, 300, 302, 312, 314, 318, 320, 324, 326, 362, 368, 372, 374, 386, 392, 396, 398, 410, 416, 420
Offset: 0

Views

Author

Antti Karttunen, Sep 22 2016

Keywords

Comments

Numbers k for which A276949(k) = 2. Starting offset is 0 (with a(0) = 2) to match with the starting offset of A273670.

Links

Crossrefs

Cf. A007623, A153880, A273670.
Row 2 of A276953, column 2 of A276955, positions of 2's in A276949.
Cf. also A276931 (terms halved).

Formula

a(n) = A153880(A273670(n)).
Showing 1-3 of 3 results.

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