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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A119202 Triangular numbers composed of digits {4,5,6}.

Original entry on oeis.org

6, 45, 55, 66, 465, 666, 4465, 4656, 5565, 6555, 46665, 544446, 4465566, 5456556, 5656566, 64564566, 4565545455565, 4664644554466, 56466665456545, 555445466565465, 555445666545666, 555665666566566, 4446456564566646, 6666664664655666, 46566644555566656
Offset: 1

Views

Author

Giovanni Resta, May 10 2006

Keywords

Links

Crossrefs

Cf. A000217, A030176, A119203. See A119033 for a table of cross-references.

Programs

  • Mathematica
    Table[Select[FromDigits/@Tuples[{4,5,6},n],OddQ[Sqrt[8#+1]]&],{n,17}]//Flatten (* Harvey P. Dale, Aug 28 2023 *)

Formula

a(n) = A000217(A119203(n)). - Tyler Busby, Mar 25 2023

Extensions

a(24)-a(25) from Tyler Busby, Mar 25 2023

A119204 Triangular numbers composed of digits {4,5,7}.

Original entry on oeis.org

45, 55, 5747745, 744574755, 77545447574475, 4745745457757444544544575, 44477447457545755547775754555, 547457575775574544754447747777455
Offset: 1

Views

Author

Giovanni Resta, May 10 2006

Keywords

Comments

a(8) > 10^40. - Tyler Busby, Mar 28 2023

Links

Crossrefs

Cf. A000217, A053951, A119205. See A119033 for a table of cross-references.

Formula

a(n) = A000217(A119205(n)). - Jon E. Schoenfield, Mar 27 2023

Extensions

a(8) from Tyler Busby, Mar 28 2023

A119206 Triangular numbers composed of digits {4,5,8}.

Original entry on oeis.org

45, 55, 48555585, 84844484544485445, 44585455858455488585854455, 445544585455555888554444445, 455888444844584444558845455, 5858855485848545848448855845485
Offset: 1

Views

Author

Giovanni Resta, May 10 2006

Keywords

Comments

a(9) > 10^40. - Tyler Busby, Mar 29 2023

Links

Crossrefs

Cf. A000217, A053953, A119207. See A119033 for a table of cross-references.

Formula

a(n) = A000217(A119207(n)). - Jon E. Schoenfield, Mar 27 2023

A119208 Triangular numbers composed of digits {4,5,9}.

Original entry on oeis.org

45, 55, 595, 5995, 49455, 55945, 594595, 5559445, 555594445, 9955945495, 55555944445, 95444955595, 5555559444445, 9545454599955, 499594959455595, 549999555454495, 555555594444445, 55555555944444445, 5555555559444444445, 5999995494459499455
Offset: 1

Views

Author

Giovanni Resta, May 10 2006

Keywords

Links

Crossrefs

Cf. A000217, A053955, A119209. See A119033 for a table of cross-references.

Programs

  • Mathematica
    Select[Flatten[Table[FromDigits/@Tuples[{4,5,9},n],{n,17}]],OddQ[ Sqrt[ 8#+1]]&] (* The program will take a long time to run. *) (* Harvey P. Dale, May 23 2021 *)

Formula

a(n) = A000217(A119209(n)). - Tyler Busby, Mar 25 2023

Extensions

a(19)-a(20) from Tyler Busby, Mar 25 2023

A119210 Triangular numbers composed of digits {4,6,7}.

Original entry on oeis.org

6, 66, 666, 476776, 764466, 4646676, 464774774646, 667474767766464747666467446, 7666777767444444644744476476, 44774674766666676747766477446
Offset: 1

Views

Author

Giovanni Resta, May 10 2006

Keywords

Comments

a(11) > 10^40. - Tyler Busby, Mar 29 2023

Links

Crossrefs

Cf. A000217, A053957, A119211. See A119033 for a table of cross-references.

Formula

a(n) = A000217(A119211(n)). - Michel Marcus, Mar 27 2023

A119212 Triangular numbers composed of digits {4,6,8}.

Original entry on oeis.org

6, 66, 666, 8646, 84666, 886446, 88864446, 646686666, 6488484486, 8888644446, 888886444446, 88888864444446, 8888888644444446, 888888886444444446, 88888888864444444446, 484888446864684484446, 8888888888644444444446, 888888888886444444444446
Offset: 1

Views

Author

Giovanni Resta, May 10 2006

Keywords

Links

Crossrefs

Cf. A000217, A053959, A119213. See A119033 for a table of cross-references.

Formula

a(n) = A000217(A119213(n)). - Michel Marcus, Mar 27 2023

Extensions

a(18) from Tyler Busby, Mar 28 2023

A119214 Triangular numbers composed of digits {4,6,9}.

Original entry on oeis.org

6, 66, 496, 666, 946, 4699966666944446964496
Offset: 1

Views

Author

Giovanni Resta, May 10 2006

Keywords

Comments

a(7) > 10^40. - Tyler Busby, Mar 29 2023

Links

Crossrefs

Cf. A000217, A053961, A119215. See A119033 for a table of cross-references.

Formula

a(n) = A000217(A119215(n)). - Michel Marcus, Mar 27 2023

A119218 Triangular numbers composed of digits {5,6,7}.

Original entry on oeis.org

6, 55, 66, 666, 5565, 6555, 5656566, 5676765, 6655776, 56567566, 575675766555, 677767555675, 555665666566566, 555667666766556, 5755656755766655, 565767676566675765, 7557657566575767666, 5555555666655656666556566566566
Offset: 1

Views

Author

Giovanni Resta, May 10 2006

Keywords

Comments

a(19) > 10^40. - Tyler Busby, Mar 28 2023

Links

Crossrefs

Cf. A000217, A053969, A119219. See A119033 for a table of cross-references.

Programs

  • Mathematica
    Select[Flatten[Table[FromDigits/@Tuples[{5,6,7},n],{n,10}]],OddQ[Sqrt[8#+1]]&] (* The program generates the first 10 terms of the sequence. *) (* Harvey P. Dale, Jan 23 2025 *)

Formula

a(n) = A000217(A119219(n)). - Michel Marcus, Mar 27 2023

Extensions

a(18) from Tyler Busby, Mar 28 2023

A119220 Triangular numbers composed of digits {5,6,8}.

Original entry on oeis.org

6, 55, 66, 666, 5565, 5886, 6555, 866586, 5656566, 5566865886, 58855888686, 866856686865, 6686866555566, 56588686866855, 88588558556655, 555665666566566, 685565588888866, 656585655585666885, 5866665855856865856556555656, 5555555666655656666556566566566, 5588888688855688866886555588568586
Offset: 1

Views

Author

Giovanni Resta, May 10 2006

Keywords

Comments

All terms except the first end in 55, 56, 65, 66, 85 or 86. - Robert Israel, Mar 26 2023

Links

Crossrefs

Cf. A000217, A119221. See A119033 for a table of cross-references.

Formula

a(n) = A000217(A119221(n)). - Tyler Busby, Mar 26 2023

Extensions

a(19)-a(21) from Tyler Busby, Mar 26 2023

A119222 Triangular numbers composed of digits {5,6,9}.

Original entry on oeis.org

6, 55, 66, 595, 666, 5565, 5995, 6555, 5656566, 95696695, 95969966995, 956996695656, 6559566959595, 59999565655666, 66555666699966, 555665666566566, 5566956999995566, 9956596655559555, 5555666996669965995, 5555555666655656666556566566566, 55659569595955595555595595599656656
Offset: 1

Views

Author

Giovanni Resta, May 10 2006

Keywords

Links

Crossrefs

Cf. A000217, A053971, A119223. See A119033 for a table of cross-references.

Formula

a(n) = A000217(A119223(n)). - Tyler Busby, Mar 26 2023

Extensions

a(19)-a(21) from Tyler Busby, Mar 26 2023
Previous Showing 91-100 of 112 results. Next

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