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 1-3 of 3 results.

A064696 Smallest value of s>0 such that A064683(s) is divisible by n, or 0 if n belongs to A064695.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 0, 6, 6, 1, 0, 16, 1, 18, 1, 6, 2, 22, 0, 0, 6, 3, 6, 28, 1, 15, 0, 2, 16, 6, 0, 3, 18, 6, 1, 5, 6, 21, 2, 1, 22, 46, 0, 42, 1, 16, 0, 13, 3, 2, 0, 18, 28, 58, 1, 60, 15, 6, 0, 6, 2
Offset: 0

Views

Author

Jonathan Ayres (jonathan.ayres(AT)btinternet.com), Oct 10 2001

Keywords

A064683 Let n(s) be the number formed from n by inserting s 0's between each digit, e.g. 123(2) is 1002003; sequence gives numbers n such that n(s) is divisible by n for some s>0.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 14, 15, 17, 18, 19, 20, 21, 22, 23, 26, 27, 28, 29, 30, 31, 33, 34, 35, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 49, 50, 51, 53, 54, 55, 57, 58, 59, 60, 61, 62, 63, 65, 66, 67, 68, 69, 70, 71, 73, 74, 77, 78, 79, 80, 81, 82, 83, 84, 85
Offset: 1

Views

Author

Jonathan Ayres (jonathan.ayres(AT)btinternet.com), Oct 10 2001

Keywords

Comments

If n=d(v)*10^v + d(v-1)*10^(v-1) .. + d(1)*10+d(0) then n(s) = d(v)*10^(v*(1+s))+d(v-1)*10^(v-1)*(1+s)+ .. + d(1)*10^(1+s)+d(0); e.g. 123(2) is 1*10^(2*3)+ 2*10^(1*3)+3*10^(0*3) = 1002003.

Examples

			a(12) = 13 because 13(6) = 10,000,003 which is divisible by 13

Crossrefs

Cf. A064695, A064696, A064697, A064698.

A106848 a(n) = the number of times the last digit of n must be appended to n to form a number m such that n divides m, or 0 if no such m exists.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 0, 6, 6, 3, 0, 16, 9, 18, 1, 6, 2, 22, 0, 0, 6, 27, 6, 28, 1, 15, 0, 2, 16, 6, 0, 3, 18, 6, 1, 5, 6, 21, 2, 9, 22, 46, 0, 42, 1, 48, 0, 13, 27, 2, 0, 18, 28, 58, 1, 60, 15, 6, 0, 6, 2, 33, 16, 22, 1, 35, 0, 8, 3, 0, 0, 2, 6, 13, 1, 81, 5, 41, 6, 16, 21, 84, 2, 44, 1
Offset: 1

Views

Author

Chuck Seggelin (seqfan(AT)plastereddragon.com), May 08 2005

Keywords

Comments

Shares many terms in common with A064696, which involved inserting zeros between digits. Numbers which do not appear to be able to form a multiple (a(n)=0) were tested out to 10000 digits added. Note those values of n for which a(n)=0 (12, 16, 24, 25, 32, 36, 48, ...) appear to be given by A064695.

Examples

			a(13) = 6 because the last digit of 13 must be appended to it six times before a new number which divides 13 is formed. (I.e., 133 mod 13 = 3, 1333 mod 13 = 7, 13333 mod 13 = 8, 133333 mod 13 = 5, 1333333 mod 13 = 6, 13333333 mod 13 = 0.) a(12)=0 because no matter how many 2's are appended to 12, the resulting number is not divisible by 12.

Crossrefs

Cf. A106849.
Showing 1-3 of 3 results.

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

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