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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A055955 a(n) = n - reversal of base 7 digits of n (written in base 10).

Original entry on oeis.org

0, 0, 0, 0, 0, 0, 0, 6, 0, -6, -12, -18, -24, -30, 12, 6, 0, -6, -12, -18, -24, 18, 12, 6, 0, -6, -12, -18, 24, 18, 12, 6, 0, -6, -12, 30, 24, 18, 12, 6, 0, -6, 36, 30, 24, 18, 12, 6, 0, 48, 0, -48, -96, -144, -192, -240, 48, 0, -48, -96, -144, -192, -240, 48, 0, -48, -96, -144, -192, -240, 48, 0, -48, -96, -144, -192, -240
Offset: 0

Views

Author

Henry Bottomley, Jul 18 2000

Keywords

Comments

a(n) is a multiple of 6.

Crossrefs

Cf. A030106, A056965.

Programs

  • Mathematica
    Table[n-FromDigits[Reverse[IntegerDigits[n,7]],7],{n,0,80}] (* Harvey P. Dale, Jul 22 2015 *)

Formula

a(n) = n - A030106(n).

A055957 n - reversal of base 8 digits of n (written in base 10).

Original entry on oeis.org

0, 0, 0, 0, 0, 0, 0, 0, 7, 0, -7, -14, -21, -28, -35, -42, 14, 7, 0, -7, -14, -21, -28, -35, 21, 14, 7, 0, -7, -14, -21, -28, 28, 21, 14, 7, 0, -7, -14, -21, 35, 28, 21, 14, 7, 0, -7, -14, 42, 35, 28, 21, 14, 7, 0, -7, 49, 42, 35, 28, 21, 14, 7, 0, 63, 0, -63, -126, -189, -252, -315, -378, 63, 0, -63, -126, -189, -252, -315
Offset: 0

Views

Author

Henry Bottomley, Jul 18 2000

Keywords

Comments

a(n) is a multiple of 7.

Crossrefs

Cf. A030107, A056965.

Programs

  • Mathematica
    Array[#-FromDigits[Reverse[IntegerDigits[#,8]],8]&,80,0] (* Harvey P. Dale, Jun 05 2012 *)

Formula

a(n) = n - A030107(n).

A055959 n - reversal of base 9 digits of n (written in base 10).

Original entry on oeis.org

0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 0, -8, -16, -24, -32, -40, -48, -56, 16, 8, 0, -8, -16, -24, -32, -40, -48, 24, 16, 8, 0, -8, -16, -24, -32, -40, 32, 24, 16, 8, 0, -8, -16, -24, -32, 40, 32, 24, 16, 8, 0, -8, -16, -24, 48, 40, 32, 24, 16, 8, 0, -8, -16, 56, 48, 40, 32, 24, 16, 8, 0, -8, 64, 56, 48, 40, 32, 24, 16, 8, 0, 80, 0, -80, -160
Offset: 0

Views

Author

Henry Bottomley, Jul 18 2000

Keywords

Comments

a(n) is a multiple of 8.

Crossrefs

Cf. A030108, A056965.

Programs

  • Mathematica
    Table[n-FromDigits[Reverse[IntegerDigits[n,9]],9],{n,0,120}] (* Harvey P. Dale, Dec 17 2022 *)

Formula

a(n) = n - A030108(n).

A055965 n - reversal of hexadecimal (base 16) digits of n (written in base 10).

Original entry on oeis.org

0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 15, 0, -15, -30, -45, -60, -75, -90, -105, -120, -135, -150, -165, -180, -195, -210, 30, 15, 0, -15, -30, -45, -60, -75, -90, -105, -120, -135, -150, -165, -180, -195, 45, 30, 15, 0, -15, -30, -45, -60, -75, -90, -105, -120, -135, -150, -165, -180, 60, 45, 30, 15, 0
Offset: 0

Views

Author

Henry Bottomley, Jul 18 2000

Keywords

Comments

a(n) is a multiple of 15

Crossrefs

Cf. A056965.

Formula

a(n) =n-A056962(n)

A055967 n - reversal of base 20 digits of n (written in base 10).

Original entry on oeis.org

0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 19, 0, -19, -38, -57, -76, -95, -114, -133, -152, -171, -190, -209, -228, -247, -266, -285, -304, -323, -342, 38, 19, 0, -19, -38, -57, -76, -95, -114, -133, -152, -171, -190, -209, -228, -247, -266, -285, -304, -323, 57, 38, 19, 0, -19, -38, -57, -76, -95
Offset: 0

Views

Author

Henry Bottomley, Jul 18 2000

Keywords

Comments

a(n) is a multiple of 19

Crossrefs

Cf. A056965.

Programs

  • Mathematica
    Table[n-FromDigits[Reverse[IntegerDigits[n,20]],20],{n,0,70}] (* Harvey P. Dale, Oct 28 2019 *)

Formula

a(n) =n-A056963(n)

A346141 Numbers k whose number of divisors equals the number of divisors in each of R(k), k+R(k), R(k+R(k)), abs(k-R(k)), and R(abs(k-R(k))), where R(m) is the digit reversal of m and where the reversals of m do not equal m.

Original entry on oeis.org

117858, 129138, 137976, 138222, 194838, 201569, 222831, 281256, 302844, 439415, 448203, 454016, 500638, 514934, 516378, 526486, 533938, 552926, 560766, 562936, 595016, 607499, 607597, 610454, 610595, 629255, 639265, 652182, 654018, 659358, 667065, 679731, 684625, 795706, 810456, 813179
Offset: 1

Views

Author

Scott R. Shannon, Jul 05 2021

Keywords

Comments

There are 324 terms below 50 million. In that range the number of divisors of the terms is 8,12,16,24,32 or 48. The first term with 8 divisors is 129138, the first with 12 is 302844, the first with 16 is 117858, the first with 24 is 138222, the first with 32 is 26739192, and the first with 48 is 19245366.

Examples

			117858 is a term as the number of divisors of 117858 = tau(117858) = 16, and this equals tau(R(117858)) = tau(858711) = 16, tau(117858+R(117858)) = tau(976569) = 16, tau(R(117858+R(117858))) = tau(965679) = 16, tau(abs(117858-R(117858))) = tau(740853) = 16, and tau(R(abs(117858-R(117858)))) = tau(358047) = 16.

Crossrefs

Cf. A000005, A004086, A346113, A056964, A056965.
Subsequence of A062895.
Previous Showing 21-26 of 26 results.

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

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