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.

A099667 a(n) is the largest prime before A002281(n); repdigits repeating 7.

Original entry on oeis.org

5, 73, 773, 7759, 77773, 777769, 7777769, 77777761, 777777773, 7777777741, 77777777767, 777777777773, 7777777777771, 77777777777753, 777777777777773, 7777777777777753, 77777777777777747, 777777777777777743
Offset: 1

Views

Author

Labos Elemer, Nov 17 2004

Keywords

Examples

			n=2: 73 is before 77.

Links

Crossrefs

Cf. A003618, A003617, A096497, A096498, A068104, A002275-A002283, A099656-A099668.

Programs

  • Mathematica
    Table[NextPrime[7 (10^n - 1)/9, -1], {n, 35}]
(* Second program: *)
Rest[NextPrime[#,-1]&/@LinearRecurrence[{11,-10},{0,7},25]] (* Harvey P. Dale, May 24 2015 *)

Extensions

Name changed by David A. Corneth, Sep 01 2017

A099658 a(n) is the smallest prime greater than 4(10^n - 1)/9.

Original entry on oeis.org

2, 5, 47, 449, 4447, 44449, 444449, 4444469, 44444453, 444444457, 4444444447, 44444444497, 444444444461, 4444444444493, 44444444444459, 444444444444461, 4444444444444463, 44444444444444461, 444444444444444469, 4444444444444444537, 44444444444444444447
Offset: 0

Views

Author

Labos Elemer, Nov 17 2004

Keywords

Comments

a(n) = smallest prime > A002278(n).

Examples

			n=4: 44 is followed by 47.

Crossrefs

Cf. A003618, A003617, A096497, A096498, A068104, A002275-A002283, A099656-A099668.

Programs

  • Mathematica
    Table[NextPrime[4*(10^n-1)/9], {n, 0, 35}]

Extensions

Checked by N. J. A. Sloane, Jan 27 2007
Mathematica program edited by Harvey P. Dale, Jul 16 2024

A099659 a(n) is the least prime following A002279(n) repdigits.

Original entry on oeis.org

7, 59, 557, 5557, 55579, 555557, 5555567, 55555559, 555555587, 5555555557, 55555555619, 555555555559, 5555555555593, 55555555555573, 555555555555557, 5555555555555573, 55555555555555639, 555555555555555559, 5555555555555555621, 55555555555555555567, 555555555555555555619
Offset: 1

Views

Author

Labos Elemer, Nov 17 2004

Keywords

Examples

			n=2: 55 is followed by 59.

Crossrefs

Cf. A003618, A003617, A096497, A096498, A068104, A002275-A002283, A099656-A099668.

Programs

  • Mathematica
    Table[NextPrime[5*(10^n-1)/9], {n, 1, 35}]

Extensions

Offset corrected by Georg Fischer, Mar 12 2024

A099660 a(n) is the least prime following A002280[n] repdigits.

Original entry on oeis.org

2, 7, 67, 673, 6673, 66683, 666667, 6666679, 66666667, 666666667, 6666666757, 66666666667, 666666666671, 6666666666683, 66666666666737, 666666666666719, 6666666666666719, 66666666666666713, 666666666666666773
Offset: 0

Views

Author

Labos Elemer, Nov 17 2004

Keywords

Examples

			n=6: 66 is followed by 67.

Crossrefs

Cf. A003618, A003617, A096497, A096498, A068104, A002275-A002283, A099656-A099668.

Programs

  • Mathematica
    Table[NextPrime[6*(10^n-1)/9], {n, 0, 35}]
NextPrime/@Table[FromDigits[PadRight[{},n,6]],{n,0,20}] (* Harvey P. Dale, Feb 25 2015 *)

Extensions

First Mathematica program corrected by Harvey P. Dale, Feb 25 2015

A099662 a(n) is the least prime following A002282(n) repdigits.

Original entry on oeis.org

2, 11, 89, 907, 8893, 88897, 888917, 8888927, 88888901, 888888901, 8888888891, 88888888901, 888888888919, 8888888888921, 88888888888889, 888888888888907, 8888888888888927, 88888888888888889, 888888888888888947
Offset: 0

Views

Author

Labos Elemer, Nov 17 2004

Keywords

Examples

			n=8: 88 is followed by 89.

Crossrefs

Cf. A003618, A003617, A096497, A096498, A068104, A002275-A002283, A099656-A099668.

Programs

  • Mathematica
    Table[NextPrime[8*(10^n-1)/9], {n, 0, 35}]

A099664 a(n) is the largest prime before A002278(n).

Original entry on oeis.org

3, 43, 443, 4441, 44417, 444443, 4444409, 44444399, 444444443, 4444444429, 44444444441, 444444444443, 4444444444439, 44444444444353, 444444444444421, 4444444444444423, 44444444444444411, 444444444444444419
Offset: 1

Views

Author

Labos Elemer, Nov 17 2004

Keywords

Examples

			n=2: 43 is before 44.

Links

Crossrefs

Cf. A003618, A003617, A096497, A096498, A068104, A002275-A002283, A099656-A099668.

Programs

  • Mathematica
    <Harvey P. Dale, Feb 25 2013 *)

A099657 a(n) is the least prime following A002277(n) repdigits.

Original entry on oeis.org

2, 5, 37, 337, 3343, 33343, 333337, 3333373, 33333347, 333333349, 3333333403, 33333333343, 333333333367, 3333333333347, 33333333333437, 333333333333389, 3333333333333343, 33333333333333391, 333333333333333391
Offset: 0

Views

Author

Labos Elemer, Nov 17 2004

Keywords

Examples

			n=3: 33 is followed by 37.

Crossrefs

Cf. A003618, A003617, A096497, A096498, A068104, A002275-A002283, A099656-A099668.

Programs

  • Mathematica
    Table[NextPrime[3*(10^n-1)/9], {n, 0, 35}]

A099661 a(n) is the least prime following A002281(n) repdigits.

Original entry on oeis.org

2, 11, 79, 787, 7789, 77783, 777781, 7777801, 77777803, 777777799, 7777777781, 77777777827, 777777777841, 7777777777859, 77777777777837, 777777777777787, 7777777777777867, 77777777777777797, 777777777777777817
Offset: 0

Views

Author

Labos Elemer, Nov 17 2004

Keywords

Examples

			n=6: 77 is followed by 79.

Crossrefs

Cf. A003618, A003617, A096497, A096498, A068104, A002275-A002283, A099656-A099668.

Programs

  • Mathematica
    Table[NextPrime[7*(10^n-1)/9], {n, 0, 35}]
NextPrime/@LinearRecurrence[{11,-10},{0,7},35] (* Harvey P. Dale, Dec 12 2021 *)

A099665 a(n) is the largest prime before A002279(n).

Original entry on oeis.org

3, 53, 547, 5531, 55547, 555523, 5555527, 55555553, 555555541, 5555555519, 55555555543, 555555555551, 5555555555551, 55555555555541, 555555555555529, 5555555555555539, 55555555555555519, 555555555555555487, 5555555555555555533, 55555555555555555483, 555555555555555555491
Offset: 1

Views

Author

Labos Elemer, Nov 17 2004

Keywords

Examples

			n=2: 53 is before 55.

Crossrefs

Cf. A002282, A003618, A003617, A007917, A096497, A096498, A068104, A002275-A002283, A099656-A099668.

Programs

  • Mathematica
    Table[NextPrime[5*(10^n-1)/9, -1], {n, 1, 35}]
NextPrime[#,-1]&/@Table[FromDigits[PadRight[{},n,5]],{n,20}] (* Harvey P. Dale, Aug 31 2015 *)

Formula

a(n) = A007917(A002282(n)). - Amiram Eldar, Jun 29 2025

A099666 a[n] is the largest prime before A002280[n] repdigits.

Original entry on oeis.org

5, 61, 661, 6661, 66653, 666649, 6666617, 66666653, 666666653, 6666666661, 66666666643, 666666666619, 6666666666629, 66666666666647, 666666666666647, 6666666666666571, 66666666666666601, 666666666666666661
Offset: 1

Views

Author

Labos Elemer, Nov 17 2004

Keywords

Examples

			n=2: 61 is before 66.

Crossrefs

Cf. A003618, A003617, A096497, A096498, A068104, A002275-A002283, A099656-A099668.

Programs

  • Mathematica
    <
Showing 1-10 of 10 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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