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 1-7 of 7 results.

A271443 Earliest start of a run of n numbers divisible by a cube larger than one.

Original entry on oeis.org

8, 80, 1375, 22624, 18035622, 4379776620, 1204244328624, 2604639091138248, 2604639091138248
Offset: 1

Views

Author

Giovanni Resta, Apr 23 2016

Keywords

Comments

a(5)-a(7) were found by Donovan Johnson.

Examples

			a(9) = 2604639091138248 and the following 8 numbers are divisible by 2^3, 11^3, 5^3, 17^3, 7^3, 13^3, 3^3, 19^3, and 2^4, respectively.
		

Crossrefs

Programs

  • Mathematica
    a[n_] := Block[{k=1, c=0}, While[ c
    				

A330480 Earliest start of a run of n numbers divisible by a fourth power larger than one.

Original entry on oeis.org

16, 80, 33614, 202099373, 40280549372, 430995495889374, 77405340617896874
Offset: 1

Views

Author

Jud McCranie, Dec 16 2019

Keywords

Comments

De Koninck's book says that "most likely" a(7)=77405340617896874.

Examples

			33614 is divisible by 7^4, 33615 is divisible by 3^4, and 33616 is divisible by 2^4.  This is the smallest number with this property, so a(3)=33614.
		

References

  • J.-M. De Koninck, Those Fascinating Numbers, Entry 242, p. 63, Amer. Math. Soc., 2009.

Crossrefs

Extensions

a(7) from Giovanni Resta, Dec 18 2019

A330481 Earliest start of a run of n numbers divisible by a fifth power larger than one.

Original entry on oeis.org

32, 1215, 2590623, 2146909373, 105636978090621, 3269698976575137500
Offset: 1

Views

Author

Jud McCranie, Dec 15 2019

Keywords

Comments

De Koninck's book gives probable a(6) = 3269698976575137500.
a(7) <= 745436945776920355709374. - Giovanni Resta, Dec 19 2019

Examples

			1215 is divisible by 3^5 and 1216 is divisible by 2^5. This is the smallest number with this property, so a(2)=1215.
		

References

  • J.-M. De Koninck, Those Fascinating Numbers, Entry 242, p. 63, Amer. Math. Soc., 2009.

Crossrefs

Extensions

a(6) from Giovanni Resta, Dec 19 2019

A330482 Earliest start of a run of n numbers divisible by a sixth power larger than one.

Original entry on oeis.org

64, 16767, 26890623, 1507545109375, 777562026420218750, 283435321166212288109372
Offset: 1

Views

Author

Jud McCranie, Dec 16 2019

Keywords

Comments

De Konnick's book gives probable terms a(5)=777562026420218750 and a(6)=283435321166212288109372.

Examples

			26890623 is divisible by 3^6, 26890624 is divisible by 2^6, and 26890625 is divisible by 5^6.  This is the smallest number with this property, so a(3) = 26890623.
		

References

  • J.-M. De Koninck, Those Fascinating Numbers, Entry 242, p. 63, Amer. Math. Soc., 2009.

Crossrefs

Extensions

a(5) from Giovanni Resta, Dec 17 2019
a(6) from Giovanni Resta, Dec 19 2019

A330484 Earliest start of a run of n numbers divisible by a ninth power larger than one.

Original entry on oeis.org

512, 3995648, 2889212890624, 18705093636361328125, 19810215665260426138787109374
Offset: 1

Views

Author

Jud McCranie, Dec 16 2019

Keywords

Comments

a(6) <= 39109788784614310863666299138574218749. - Robert Israel, Jun 02 2020

Examples

			2889212890624 is divisible by 2^9, 2889212890625 is divisible by 5^9, and 2889212890626 is divisible by 3^9. This is the smallest number with this property, so a(3)=2889212890624.
		

Crossrefs

Extensions

a(4)-a(5) from Giovanni Resta, Dec 17 2019

A330485 Earliest start of a run of n numbers divisible by a tenth power larger than one.

Original entry on oeis.org

1024, 24151040, 61938212890624, 9226967798833574218749, 13279660499584033124533574218748
Offset: 1

Views

Author

Jud McCranie, Dec 16 2019

Keywords

Examples

			61938212890624 is divisible by 2^10, 61938212890625 is divisible by 5^10, and 61938212890626 is divisible by 3^10.  This is the smallest number with this property, so a(3)=61938212890624.
		

Crossrefs

Extensions

a(4) from Giovanni Resta, Dec 17 2019
a(5) from Giovanni Resta, Dec 19 2019

A088080 Start of n successive numbers divisible by n-th powers.

Original entry on oeis.org

1, 8, 1375, 202099373, 105636978090621, 283435321166212288109372
Offset: 1

Views

Author

Amarnath Murthy, Sep 22 2003

Keywords

Comments

a(5) <= 105636978090621.

Examples

			a(3)=1375 because 1375=5^3*11, 1376=2^3*172, 1377=3^3*51; all multiples of cubes.
		

Crossrefs

Extensions

Corrected and extended by Don Reble, Sep 27 2003
a(5) from Donovan Johnson, Dec 14 2010
a(6) from Giovanni Resta, Dec 19 2019
Showing 1-7 of 7 results.