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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A051849 Table in which n-th row gives all compositions of n interpreted as digits in base n+1.

Original entry on oeis.org

1, 2, 4, 3, 6, 9, 21, 4, 8, 12, 16, 32, 36, 56, 156, 5, 10, 15, 20, 25, 45, 50, 55, 80, 85, 115, 260, 265, 295, 475, 1555, 6, 12, 18, 24, 30, 36, 60, 66, 72, 78, 108, 114, 120, 156, 162, 204, 402, 408, 414, 450, 456, 498, 744, 750, 792, 1086, 2802, 2808, 2850, 3144
Offset: 1

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Author

Antti Karttunen, Dec 13 1999

Keywords

Comments

All terms on row n are divisible by n. See A051850.

Examples

			n-th row has length 2^(n-1) (A000079[n-1]) 1; 2, 4; 3, 6, 9, 21; 4, 8, 12, 16, 32, 36, 56, 156; 3 can be written as sum like 3, or 1+2 or 2+1 or 1+1+1. Numbers 3, 12, 21 and 111 interpreted in base 4 give the third row of table: 3,6,9,21
		

Crossrefs

Cf. A051850, A051851, ...
Cf. A124734.

Programs

  • Maple
    with(combinat); rows_upto_u := proc(u) local a,n; a := []; for n from 1 to u do a := [op(a),op(sort(map(list_in_base_b,map(op,map(permute,partition(n))),(n+1))))]; od; RETURN(a); end; # list_in_base_b given in A051845.

Extensions

Definition corrected by Franklin T. Adams-Watters, Nov 20 2006

A051852 A051851(n)/row_index_of(n).

Original entry on oeis.org

1, 1, 2, 1, 2, 7, 1, 2, 3, 8, 39, 1, 2, 3, 9, 10, 52, 311, 1, 2, 3, 4, 10, 11, 19, 67, 68, 467, 3268, 1, 2, 3, 4, 11, 12, 13, 21, 84, 85, 94, 669, 670, 5350, 42799, 1, 2, 3, 4, 5, 12, 13, 14, 23, 24, 103, 104, 105, 114, 205, 923, 924, 934, 8304, 8305, 74734, 672605, 1, 2, 3
Offset: 1

Views

Author

Antti Karttunen, Dec 13 1999

Keywords

Examples

			1; 1, 2; 1, 2, 7; 1, 2, 3, 8, 39; 1, 2, 3, 9, 10, 52, 311;
		

Crossrefs

A subset of A051850 (but note the relative indexing...)

Programs

  • Maple
    with(combinat); rows_upto_u := proc(u) local a,n; a := []; for n from 1 to u do a := [op(a),op(map(divby, sort(map(list_in_base_b,partition(n),(n+1))), n))]; od; RETURN(a); end;
Showing 1-2 of 2 results.