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 1-4 of 4 results.

A157451 Number generated by regarding the numbers in row n of A139038 as digits of a base n number.

Original entry on oeis.org

1, 3, 13, 85, 806, 9583, 140050, 2434185, 49031983, 1122332211, 28768909071, 816222524845, 25389827448220, 859153189293015, 31417769545499716, 1234605616147931665, 51882038993710230701, 2321660210597147557819
Offset: 1

Views

Author

Roger L. Bagula, Mar 01 2009

Keywords

Examples

			Row 5 of A139038 is 1,1,2,1,1. 11211 in base 5 = 5^4 + 5^3 + 2*5^2 + 5 + 1 = 806, so a(5) = 806.
		

Crossrefs

Programs

  • Mathematica
    t[n_, m_] = Min[Floor[(m+1)/2], 1 + Floor[(n - m)/2]];
    Table[FromDigits[{Table[t[n, m], {m, 1, n}], n}, n], {n, 1, 21}]

Formula

t(n,m)== Min[1 + Floor[m/2], 1 + Floor[(n - m)/2]]; a(n)=FromDigits[{Table[t[n, m], {m, 0, n}], n + 1}, n + 1].

Extensions

Edited by Franklin T. Adams-Watters, Sep 25 2011

A157457 Read n-th row of triangle in A157458 and regard it as the expansion of a number in base n+1.

Original entry on oeis.org

0, 3, 16, 125, 1116, 12943, 182400, 3080025, 60524200, 1357997531, 34237168560, 957927505717, 29446184348868, 986272776455415, 35746439807927296, 1393753996031259953, 58165330905054360720, 2586788074128361802419
Offset: 0

Views

Author

Roger L. Bagula, Mar 01 2009

Keywords

Crossrefs

Programs

  • Mathematica
    t[n_, m_] =Min[1 + 2*m, 1 + 2*(n - m), n];
    Table[FromDigits[{Table[t[n, m], {m, 0, n}], n + 1}, n + 1], {n, 0, 20}]

Extensions

Edited by N. J. A. Sloane, Aug 27 2009

A157452 Number generated by regarding the numbers in row n of A003983 as digits of a base n number.

Original entry on oeis.org

1, 3, 16, 105, 961, 11137, 160000, 2738385, 54479161, 1234554321, 31384248336, 884241045961, 27342890695849, 920521266133785, 33512287502995456, 1311768467139281697, 54933923639963082961, 2450641333396432006369
Offset: 1

Views

Author

Roger L. Bagula, Mar 01 2009

Keywords

Comments

We are regarding A003983 as a triangle, not as an array by antidiagonals.

Examples

			Row 4 of A003983 is 1,2,2,1. The number 1221 in base 4 is 4^3 + 2*4^2 + 2*4 + 1 = 105, so a(4) = 105.
		

Crossrefs

Programs

  • Mathematica
    t[n_, m_] =Min[m, n - m + 1];
    Table[FromDigits[{Table[t[n, m], {m, 1, n}], n}, n], {n, 1, 21}]

Formula

t(n,m)=Min[1 + m, 1 + (n - m)]; a(n)=FromDigits[{Table[t[n, m], {m, 0, n}], n + 1}, n + 1].

Extensions

Edited by Franklin T. Adams-Watters, Sep 25 2011

A157455 Number generated by regarding the numbers in row n of A157454 as digits of a base n number.

Original entry on oeis.org

1, 3, 19, 125, 1141, 12943, 182743, 3080025, 60530761, 1357997531, 34237329611, 957927505717, 29446189175677, 986272776455415, 35746439978786671, 1393753996031259953, 58165330912030118161, 2586788074128361802419
Offset: 1

Views

Author

Roger L. Bagula, Mar 01 2009

Keywords

Comments

Note that for odd n, the digits will include n itself.

Examples

			Row 4 of A157454 is 1,3,3,1. 1331 in base 4 = 4^3 + 3*4^2 + 3*4 + 1 = 125, so a(4) = 125.
		

Crossrefs

Programs

  • Mathematica
    t[n_, m_] =Min[1 + 2*m, 1 + 2*(n - m)];
    Table[FromDigits[{Table[t[n, m], {m, 0, n}], n + 1}, n + 1], {n, 0, 20}]

Formula

t(n,m)=Min[2*m - 1, 2*(n - m) + 1]; a(n)=FromDigits[{Table[t[n, m], {m, 1, n}], n}, n].

Extensions

Edited by Franklin T. Adams-Watters, Sep 25 2011
Showing 1-4 of 4 results.