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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.

A265146 Triangle T(n,k) in which n-th row lists the parts i_1=1, 1<=k<=A001222(n).

Original entry on oeis.org

1, 2, 1, 2, 3, 1, 3, 4, 1, 2, 3, 2, 3, 1, 4, 5, 1, 2, 4, 6, 1, 5, 2, 4, 1, 2, 3, 4, 7, 1, 3, 4, 8, 1, 2, 5, 2, 5, 1, 6, 9, 1, 2, 3, 5, 3, 4, 1, 7, 2, 3, 4, 1, 2, 6, 10, 1, 3, 5, 11, 1, 2, 3, 4, 5, 2, 6, 1, 8, 3, 5, 1, 2, 4, 5, 12, 1, 9, 2, 7, 1, 2, 3, 6, 13, 1
Offset: 1

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Author

Alois P. Heinz, Dec 02 2015

Keywords

Comments

A strict partition is a partition into distinct parts.
Row n=1 contains the parts of the empty partition, so it is empty.

Examples

			n = 12 = 2*2*3 = prime(1)*prime(1)*prime(2) encodes strict partition [1,2,4].
Triangle T(n,k) begins:
01 :  ;
02 :  1;
03 :  2;
04 :  1, 2;
05 :  3;
06 :  1, 3;
07 :  4;
08 :  1, 2, 3;
09 :  2, 3;
10 :  1, 4;
11 :  5;
12 :  1, 2, 4;
13 :  6;
14 :  1, 5;
15 :  2, 4;
16 :  1, 2, 3, 4;
		

Crossrefs

Column k=1 gives A055396 (for n>1).
Last terms of rows give A252464 (for n>1).
Row sums give A266475.

Programs

  • Maple
    T:= n-> ((l-> seq(l[j]+j-1, j=1..nops(l)))(sort([seq(
           numtheory[pi](i[1])$i[2], i=ifactors(n)[2])]))):
    seq(T(n), n=1..100);
  • Mathematica
    T[n_] := Function[l, Table[l[[j]]+j-1, {j, 1, Length[l]}]][Sort[ Flatten[ Table[ Array[ PrimePi[i[[1]]]&, i[[2]]], {i, FactorInteger[n]}]]]];
    Table[T[n], {n, 1, 100}] // Flatten // Rest (* Jean-François Alcover, Mar 23 2017, translated from Maple *)

Formula

T(prime(n),1) = n.