A298422 -id:A298422 - cp's OEIS frontend

A298479 Matula-Goebel numbers of rooted trees in which all positive outdegrees are different.

1, 2, 4, 6, 7, 8, 12, 16, 19, 24, 28, 32, 38, 42, 48, 52, 53, 56, 57, 64, 68, 74, 84, 96, 104, 106, 107, 112, 128, 131, 134, 136, 152, 159, 163, 168, 178, 192, 208, 212, 224, 228, 256, 262, 263, 272, 296, 304, 311, 318, 336, 356, 384, 393, 416, 446, 448, 456

Offset: 1

Gus Wiseman, Jan 19 2018

nonn

			Sequence of trees begins:
1  o
2  (o)
4  (oo)
6  (o(o))
7  ((oo))
8  (ooo)
12 (oo(o))
16 (oooo)
19 ((ooo))
24 (ooo(o))
28 (oo(oo))
32 (ooooo)
38 (o(ooo))
42 (o(o)(oo))
48 (oooo(o))
52 (oo(o(o)))
53 ((oooo))
56 (ooo(oo))
57 ((o)(ooo))
64 (oooooo)
68 (oo((oo)))
74 (o(oo(o)))
84 (oo(o)(oo))
96 (ooooo(o))

Cf. A000081, A001221, A004111, A007097, A032305, A061775, A111299, A276625, A290760, A297571, A298120, A298422, A298424, A298478.

MGtree[n_]:=If[n===1,{},MGtree/@Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
doQ[n_]:=Or[n===1,UnsameQ@@Length/@Cases[MGtree[n],{},{0,Infinity}]];
Select[Range[1000],doQ]

A301367 Regular triangle where T(n,k) is the number of orderless same-trees of weight n with k leaves.

Original entry on oeis.org

1, 1, 1, 1, 0, 1, 1, 1, 1, 2, 1, 0, 0, 0, 1, 1, 1, 1, 2, 1, 3, 1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 3, 4, 4, 3, 5, 1, 0, 1, 0, 1, 0, 1, 0, 2, 1, 1, 0, 0, 1, 2, 1, 1, 1, 3, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 2, 4, 5, 10, 11, 14, 12, 14, 7, 13, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 1

Offset: 1

Gus Wiseman, Mar 19 2018

An orderless same-tree of weight n > 0 is either a single node of weight n, or a finite multiset of two or more orderless same-trees whose weights are all the same and sum to n.

			Triangle begins:
1
1   1
1   0   1
1   1   1   2
1   0   0   0   1
1   1   1   2   1   3
1   0   0   0   0   0   1
1   1   1   3   4   4   3   5
1   0   1   0   1   0   1   0   2
1   1   0   0   1   2   1   1   1   3
1   0   0   0   0   0   0   0   0   0   1
1   1   2   4   5  10  11  14  12  14   7  13
1   0   0   0   0   0   0   0   0   0   0   0   1
1   1   0   0   0   0   1   2   1   1   1   1   1   3
The T(8,5) = 4 orderless same-trees: (4((11)(11))), (4(1111)), ((22)(2(11))), (222(11)).

Andrew Howroyd, Table of n, a(n) for n = 1..1275 (rows 1..50)

Last entries of each row give A289079. Row sums are A289078.

Cf. A003238, A006241, A008284, A055277, A063834, A273873, A281145, A289501, A294080, A298422, A298426, A299201, A299203, A301343, A301364-A301368.

olstrees[n_]:=Prepend[Join@@Table[Select[Tuples[olstrees/@ptn],OrderedQ],{ptn,Select[IntegerPartitions[n],Length[#]>1&&SameQ@@#&]}],n];
Table[Length[Select[olstrees[n],Count[#,_Integer,{-1}]===k&]],{n,14},{k,n}]

S(g, k)={polcoef(exp(sum(i=1, k, x^i*subst(g, y, y^i)/i) + O(x*x^k)), k)}
A(n)={my(v=vector(n)); for(n=1, n, v[n] = y + sumdiv(n, d, S(v[n/d], d))); apply(p -> Vecrev(p/y), v)}
{ my(v=A(16)); for(n=1, #v, print(v[n])) } \\ Andrew Howroyd, Aug 20 2018

A301366 Regular triangle where T(n,k) is the number of same-trees of weight n with k leaves.

Original entry on oeis.org

1, 1, 1, 1, 0, 1, 1, 1, 2, 2, 1, 0, 0, 0, 1, 1, 1, 1, 5, 3, 3, 1, 0, 0, 0, 0, 0, 1, 1, 1, 2, 6, 12, 14, 12, 6, 1, 0, 1, 0, 3, 0, 3, 0, 2, 1, 1, 0, 0, 1, 7, 10, 10, 5, 3, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 3, 7, 21, 41, 58, 100, 100, 94, 48, 20

Offset: 1

Gus Wiseman, Mar 19 2018

A same-tree of weight n > 0 is either a single node of weight n, or a finite sequence of two or more same-trees whose weights are all the same and sum to n.

			Triangle begins:
1
1   1
1   0   1
1   1   2   2
1   0   0   0   1
1   1   1   5   3   3
1   0   0   0   0   0   1
1   1   2   6  12  14  12   6
1   0   1   0   3   0   3   0   2
1   1   0   0   1   7  10  10   5   3
1   0   0   0   0   0   0   0   0   0   1
1   1   3   7  21  41  58 100 100  94  48  20
The T(8,4) = 6 same-trees: (4(2(11))), (4((11)2)), ((22)(22)), ((2(11))4), (((11)2)4), (2222).

Andrew Howroyd, Table of n, a(n) for n = 1..1275 (rows 1..50)

Last entries of each row give A006241. Row sums are A281145.

Cf. A003238, A008284, A055277, A063834, A273873, A289501, A294080, A298422, A298426, A299201, A299203, A300442, A300443, A301343, A301364-A301368.

sametrees[n_]:=Prepend[Join@@Table[Tuples[sametrees/@ptn],{ptn,Select[IntegerPartitions[n],Length[#]>1&&SameQ@@#&]}],n];
Table[Length[Select[sametrees[n],Count[#,_Integer,{-1}]===k&]],{n,12},{k,n}]

A(n)={my(v=vector(n)); for(n=1, n, v[n] = x + sumdiv(n, d, v[n/d]^d)); apply(p -> Vecrev(p/x), v)}
{my(v=A(16)); for(n=1, #v, print(v[n]))} \\ Andrew Howroyd, Aug 20 2018

cp's OEIS Frontend

A298479 Matula-Goebel numbers of rooted trees in which all positive outdegrees are different.

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A301367 Regular triangle where T(n,k) is the number of orderless same-trees of weight n with k leaves.

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Keywords

Comments

Examples

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Crossrefs

Programs

Mathematica

PARI

A301366 Regular triangle where T(n,k) is the number of same-trees of weight n with k leaves.

Views

Author

Keywords

Comments

Examples

Links

Crossrefs

Programs

Mathematica

PARI