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.

Previous Showing 11-18 of 18 results.

A167886 n-th single or isolated number minus n-th non-single or nonisolated number.

Original entry on oeis.org

2, 3, 3, 7, 11, 15, 21, 27, 31, 34, 39, 45, 51, 55, 60, 63, 68, 75, 78, 83, 87, 100, 103, 109, 119, 125, 130, 133, 138, 144, 154, 159, 171, 182, 185, 189, 195, 205, 209, 214, 220, 226, 230, 239, 252, 256, 260, 273, 278, 287, 291, 296, 303, 308, 313, 315, 320, 327
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Nov 14 2009

Keywords

Examples

			a(1)=2-0=2, a(2)=4-1=3, a(3)=6-3=3, a(4)=12-5=7.

Crossrefs

Cf. A167706, A167707.

Formula

a(n)=A167706(n)-A167707(n).

Extensions

All numbers > 68 corrected by R. J. Mathar, May 30 2010

A167887 n-th single or isolated number plus n-th non-single or nonisolated number.

Original entry on oeis.org

2, 5, 9, 17, 25, 31, 39, 47, 53, 60, 67, 75, 83, 89, 98, 103, 110, 119, 126, 133, 139, 154, 159, 167, 181, 189, 196, 201, 208, 216, 230, 237, 251, 264, 271, 277, 285, 297, 305, 312, 320, 328, 334, 347, 362, 368, 374, 389, 396, 409, 415, 422, 431, 438, 445, 451
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Nov 14 2009

Keywords

Examples

			a(1)=2+0=2, a(2)=4+1=5, a(3)=6+3=9, a(4)=12+5=17.

Crossrefs

Cf. A167706, A167707.

Formula

a(n)=A167706(n)+A167707(n).

Extensions

All terms > 110 corrected by R. J. Mathar, May 30 2010

A167888 n-th single or isolated number^n-th non-single or nonisolated number.

Original entry on oeis.org

1, 4, 216, 248832, 612220032, 78310985281, 19683000000000, 4808584372417849, 717368321110468608, 5460999706120583177327, 1379946262057143768386569, 470184984576000000000000000, 164890958756244164895763202881
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Nov 14 2009

Keywords

Examples

			a(1)=2^0=1, a(2)=4^1=4, a(3)=6^3=216, a(4)=12^5=248832.

Crossrefs

Cf. A167706, A167707.

Formula

a(n)=A167706(n)^A167707(n).

Extensions

More terms from R. J. Mathar, May 30 2010

A168241 n-th squarefree number plus n-th non-single or nonisolated number.

Original entry on oeis.org

1, 3, 6, 10, 13, 15, 19, 21, 24, 27, 29, 32, 35, 38, 41, 43, 47, 51, 54, 56, 59, 61, 63, 66, 69, 71, 74, 76, 78, 82, 85, 90, 93, 96, 100, 102, 104, 107, 110, 114, 116, 118, 121, 124, 126, 129, 131, 135, 137, 140, 144, 146, 149, 151, 153, 157, 160, 163, 165, 168, 171
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Nov 21 2009

Keywords

Formula

a(n)=A005117(n)+A167707(n).

A168350 Sum of first n non-single or nonisolated numbers.

Original entry on oeis.org

0, 1, 4, 9, 16, 24, 33, 43, 54, 67, 81, 96, 112, 129, 148, 168, 189, 211, 235, 260, 286, 313, 341, 370, 401, 433, 466, 500, 535, 571, 609, 648, 688, 729, 772, 816, 861, 907, 955, 1004, 1054, 1105, 1157, 1211, 1266, 1322, 1379, 1437, 1496, 1557, 1619, 1682
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Nov 23 2009

Keywords

Examples

			a(1)=0, a(2)=0+1=1, a(3)=0+1+3=4.

Crossrefs

Cf. A167707.

Formula

a(n)=sum{j=1..n} A167707(j).

Extensions

Formula and A-number corrected and entries checked by R. J. Mathar, Nov 24 2009

A168496 The positions of non-single or nonisolated numbers in A001477.

Original entry on oeis.org

1, 2, 4, 6, 8, 9, 10, 11, 12, 14, 15, 16, 17, 18, 20, 21, 22, 23, 25, 26, 27, 28, 29, 30, 32, 33, 34, 35, 36, 37, 39, 40, 41, 42, 44, 45, 46, 47, 49, 50, 51, 52, 53, 55, 56, 57, 58, 59, 60, 62, 63, 64, 65, 66, 67, 69, 70, 71, 72, 74, 75, 76, 77, 78, 79, 81, 82, 83, 85, 86, 87
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Nov 27 2009

Keywords

Crossrefs

Cf. A001477, A167707.

Formula

a(n) = 1+A167707(n).

Extensions

Formula corrected by R. J. Mathar, Jun 04 2010

A168498 The positions of non-single or nonisolated numbers in A000010.

Original entry on oeis.org

1, 2, 11, 15, 16, 17, 20, 22, 23, 24, 25, 29, 30, 32, 33, 34, 35, 37, 39, 40, 41, 44, 45, 46, 47, 48, 50, 51, 52, 53, 55, 56, 57, 58, 59, 60, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 74, 75, 76, 78, 79, 80, 81, 82, 83, 84, 85, 87, 88, 89, 90, 92, 94, 96, 97, 100, 101, 102, 104
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Nov 27 2009

Keywords

Comments

Numbers n such that phi(n)=non-single or nonisolated number.

Crossrefs

Cf. A000010, A167707.

Extensions

Extended by R. J. Mathar, Nov 30 2009

A171433 n-th half of even single (or even isolated) numbers plus n-th half of even non-single (or even nonisolated) numbers.

Original entry on oeis.org

1, 6, 8, 13, 17, 25, 32, 42, 49, 65, 70, 86, 93, 109, 116, 121, 137, 144, 160, 167, 183, 202, 239, 247, 263, 294, 319, 335, 346, 359, 369, 445, 452, 456, 472, 485, 555, 562, 572, 579, 595, 626, 667, 692, 700, 707, 717, 772, 785, 801, 805, 866, 873, 898, 914
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Dec 09 2009

Keywords

Examples

			a(1)=1+0=1, a(2)=2+4=6, a(3)=3+5=8.

Crossrefs

Cf. A167706(the single or isolated numbers), A167707(the non-single or nonisolatred numbers), A168044, A168497.

Formula

a(n)=A168497(n)+A168044(n).

Extensions

Entries checked by R. J. Mathar, May 23 2010
Previous Showing 11-18 of 18 results.

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