A059966
a(n) = (1/n) * Sum_{ d divides n } mu(n/d) * (2^d - 1).
Original entry on oeis.org
1, 1, 2, 3, 6, 9, 18, 30, 56, 99, 186, 335, 630, 1161, 2182, 4080, 7710, 14532, 27594, 52377, 99858, 190557, 364722, 698870, 1342176, 2580795, 4971008, 9586395, 18512790, 35790267, 69273666, 134215680, 260300986, 505286415, 981706806
Offset: 1
a(4)=3: the 3 elements [a,c], [a[a,b]] and d form a basis of all homogeneous elements of degree 4 in the free Lie algebra with generators a of degree 1, b of degree 2, c of degree 3 and d of degree 4.
From _Gus Wiseman_, Dec 19 2017: (Start)
The sequence of Lyndon compositions organized by sum begins:
(1),
(2),
(3),(12),
(4),(13),(112),
(5),(14),(23),(113),(122),(1112),
(6),(15),(24),(114),(132),(123),(1113),(1122),(11112),
(7),(16),(25),(115),(34),(142),(124),(1114),(133),(223),(1213),(1132),(1123),(11113),(1222),(11212),(11122),(111112). (End)
- C. Reutenauer, Free Lie algebras, Clarendon press, Oxford (1993).
- Reinhard Zumkeller, Table of n, a(n) for n = 1..1000
- Nicolas Andrews, Lucas Gagnon, Félix Gélinas, Eric Schlums, and Mike Zabrocki, When are Hopf algebras determined by integer sequences?, arXiv:2505.06941 [math.CO], 2025. See p. 17.
- S. V. Duzhin and D. V. Pasechnik, Groups acting on necklaces and sandpile groups, Journal of Mathematical Sciences, August 2014, Volume 200, Issue 6, pp 690-697. See page 85. - N. J. A. Sloane, Jun 30 2014
- Seok-Jin Kang and Myung-Hwan Kim, Free Lie Algebras, Generalized Witt Formula and the Denominator Identity, Journal of Algebra 183, 560-594 (1996).
- Michael J. Mossinghoff and Timothy S. Trudgian, A tale of two omegas, arXiv:1906.02847 [math.NT], 2019.
- G. Niklasch, Some number theoretical constants: 1000-digit values [Cached copy]
- Jakob Oesinghaus, Quasi-symmetric functions and the Chow ring of the stack of expanded pairs, arXiv:1806.10700 [math.AG], 2018.
- Robert Schneider, Andrew V. Sills, and Hunter Waldron, On the q-factorization of power series, arXiv:2501.18744 [math.CO], 2025. See p. 6.
Apart from initial terms, same as
A001037.
Cf.
A000225,
A000740,
A008683,
A008965,
A011782,
A060223,
A185700,
A228369,
A269134 A281013,
A296302,
A296373.
-
a059966 n = sum (map (\x -> a008683 (n `div` x) * a000225 x)
[d | d <- [1..n], mod n d == 0]) `div` n
-- Reinhard Zumkeller, Nov 18 2011
-
Table[1/n Apply[Plus, Map[(MoebiusMu[n/# ](2^# - 1)) &, Divisors[n]]], {n, 20}]
(* Second program: *)
Table[(1/n) DivisorSum[n, MoebiusMu[n/#] (2^# - 1) &], {n, 35}] (* Michael De Vlieger, Jul 22 2019 *)
-
from sympy import mobius, divisors
def A059966(n): return sum(mobius(n//d)*(2**d-1) for d in divisors(n,generator=True))//n # Chai Wah Wu, Feb 03 2022
Description corrected by Axel Kleinschmidt, Sep 15 2002
A102659
List of Lyndon words on {1,2} sorted first by length and then lexicographically.
Original entry on oeis.org
1, 2, 12, 112, 122, 1112, 1122, 1222, 11112, 11122, 11212, 11222, 12122, 12222, 111112, 111122, 111212, 111222, 112122, 112212, 112222, 121222, 122222, 1111112, 1111122, 1111212, 1111222, 1112112, 1112122, 1112212, 1112222, 1121122
Offset: 1
- Reinhard Zumkeller, Table of n, a(n) for n = 1..10000
- F. Bassino, J. Clement and C. Nicaud, The standard factorization of Lyndon words: an average point of view, Discrete Math. 290 (2005), 1-25.
- Émilie Charlier, Manon Philibert, Manon Stipulanti, Nyldon words, arXiv:1804.09735 [math.CO], 2018. See Table 1.
- A. M. Uludag, A. Zeytin and M. Durmus, Binary Quadratic Forms as Dessins, 2012. - From _N. J. A. Sloane_, Dec 31 2012
- Wikipedia, Lyndon word
- Reinhard Zumkeller, Haskell programs for some sequences concerning Lyndon words
- Index entries for sequences related to Lyndon words
A sequence listing all Lyndon compositions is
A294859.
Numbers whose binary expansion is Lyndon are
A328596.
Length of the Lyndon factorization of the binary expansion is
A211100.
-
cf. link.
-
lynQ[q_]:=Array[Union[{q,RotateRight[q,#]}]=={q,RotateRight[q,#]}&,Length[q]-1,1,And];
Join@@Table[FromDigits/@Select[Tuples[{1,2},n],lynQ],{n,5}] (* Gus Wiseman, Nov 14 2019 *)
-
is_A102659(n)={ vecsort(d=digits(n))!=d&&for(i=1,#d-1, n>[1,10^(#d-i)]*divrem(n,10^i)&&return); fordiv(#d,L,L<#d && d==concat(Col(vector(#d/L,i,1)~*vecextract(d,2^L-1))~)&&return); !setminus(Set(d),[1,2])} \\ The last check is the least expensive one, but not useful if we test only numbers with digits {1,2}.
for(n=1,6,p=vector(n,i,10^(n-i))~;forvec(d=vector(n,i,[1,2]),is_A102659(m=d*p)&&print1(m","))) \\ One could use is_A102660 instead of is_A102659 here. - M. F. Hasler, Mar 08 2014
A185700
The number of periods in a reshuffling operation for compositions of n.
Original entry on oeis.org
1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 2, 2, 1, 0, 1, 2, 3, 2, 1, 0, 1, 3, 5, 5, 3, 1, 0, 1, 3, 7, 8, 7, 3, 1, 0, 1, 4, 9, 14, 14, 9, 4, 1, 0, 1, 4, 12, 20, 25, 20, 12, 4, 1, 0, 1, 5, 15, 30, 42, 42, 30, 15, 5, 1, 0, 1, 5, 18, 40, 66, 75, 66, 40, 18, 5, 1, 0, 1, 6, 22, 55, 99, 132, 132, 99, 55, 22, 6, 1, 0, 1, 6, 26, 70, 143, 212, 245, 212, 143, 70, 26, 6, 1
Offset: 1
For k=5: T(4)=10 < n < T(5)=15 and all periods are of length 5:
a(11)=1 period: [(4+3+2+1+1), (4+3+2+2), (4+3+3+1), (4+4+2+1), (5+3+2+1)];
a(12)=2 periods: [(4+3+2+2+1), (4+3+3+2), (4+4+3+1), (5+4+2+1), (5+3+2+1+1)]; and [(4+4+2+2), (5+3+3+1), (4+4+2+1+1), (5+3+2+2), (4+3+3+1+1)];
a(13)=2 periods: [(4+4+2+2+1), (5+3+3+2), (4+4+3+1+1), (5+4+2+2), (5+3+3+1+1)]; and [(5+4+3+1), (5+4+2+1+1), (5+3+2+2+1), (4+3+3+2+1), (4+4+3+2)];
a(14)=1 period: [(5+4+3+2), (5+4+3+1+1), (5+4+2+2+1), (5+3+3+2+1), (4+4+3+2+1)].
For k=16; j=8; n=T(k-1)+j=128; 1<q|(16,8) --> {2,4,8} a(128) = c(128) - a(T(7)+4) - a(T(3)+2) - a(T(1)+1) = 810 - 8 - 1 - 1 = 800.
(binomial(16,8)-8*a(T(7)+4)-4*a(T(3)+2)-2*a(T(1)+1))/16 = (12870-64-4-2)/16 = 800 = a(128).
Triangular view, with a(n) distributed in rows k=1,2,3.. according to T(k-1)< n <= T(k):
1; k=1, n=1
1, 0; k=2, n=2..3
1, 1, 0; k=3, n=4..6
1, 1, 1, 0; k=4, n=7..10
1, 2, 2, 1, 0; k=5, n=11..15
1, 2, 3, 2, 1, 0; k=6, n=16..21
1, 3, 5, 5, 3, 1, 0;
1, 3, 7, 8, 7, 3, 1, 0;
1, 4, 9, 14, 14, 9, 4, 1, 0;
1, 4, 12, 20, 25, 20, 12, 4, 1, 0;
1, 5, 15, 30, 42, 42, 30, 15, 5, 1, 0;
1, 5, 18, 40, 66, 75, 66, 40, 18, 5, 1, 0;
1, 6, 22, 55, 99, 132, 132, 99, 55, 22, 6, 1, 0;
1, 6, 26, 70, 143, 212, 245, 212, 143, 70, 26, 6, 1, 0;
- R. Baumann, Computer-Knobelei, LOGIN (1987), 483-486 (in German).
Cf.
A000740,
A001037,
A008965,
A051168,
A059966,
A060223,
A245558,
A294859,
A296302,
A296373,
A092964,
A245559,
A245558.
-
A000217 := proc(n) n*(n+1)/2 ; end proc:
A185700 := proc(n) local k,j,a,q; k := ceil( (-1+sqrt(1+8*n))/2 ) ; j := n-A000217(k-1) ; if n = 1 then return 1; elif j = k then return 0 ; end if; a := binomial(k,j) ; if not isprime(k) then for q in numtheory[divisors]( igcd(k,j)) minus {1} do a := a- procname(j/q+A000217(k/q-1))*k/q ; end do: end if; a/k ; end proc:
seq(A185700(n),n=1..80) ; # R. J. Mathar, Jun 11 2011
-
LyndonQ[q_]:=Array[OrderedQ[{q,RotateRight[q,#]}]&,Length[q]-1,1,And]&&Array[RotateRight[q,#]&,Length[q],1,UnsameQ];
Table[Length@Select[Join@@Permutations/@Select[IntegerPartitions[n],Length[#]===k&],LyndonQ],{n,10},{k,n}] (* Gus Wiseman, Dec 19 2017 *)
A296372
Triangle read by rows: T(n,k) is the number of normal sequences of length n whose standard factorization into Lyndon words (aperiodic necklaces) has k factors.
Original entry on oeis.org
1, 1, 2, 4, 5, 4, 18, 31, 18, 8, 108, 208, 153, 56, 16, 778, 1700, 1397, 616, 160, 32, 6756, 15980, 14668, 7197, 2196, 432, 64, 68220, 172326, 171976, 93293, 31564, 7208, 1120, 128
Offset: 1
The T(3,2) = 5 normal sequences are {2,1,2}, {1,2,1}, {2,1,3}, {2,3,1}, {3,1,2}.
Triangle begins:
1;
1, 2;
4, 5, 4;
18, 31, 18, 8;
108, 208, 153, 56, 16;
778, 1700, 1397, 616, 160, 32;
6756, 15980, 14668, 7197, 2196, 432, 64;
Cf.
A000740,
A001045,
A008965,
A019536,
A059966,
A074650,
A185700,
A228369,
A232472,
A277427,
A281013,
A296373.
-
neckQ[q_]:=Array[OrderedQ[{q,RotateRight[q,#]}]&,Length[q]-1,1,And];
aperQ[q_]:=UnsameQ@@Table[RotateRight[q,k],{k,Length[q]}];
qit[q_]:=If[#===Length[q],{q},Prepend[qit[Drop[q,#]],Take[q,#]]]&[Max@@Select[Range[Length[q]],neckQ[Take[q,#]]&&aperQ[Take[q,#]]&]];
allnorm[n_]:=Function[s,Array[Count[s,y_/;y<=#]+1&,n]]/@Subsets[Range[n-1]+1];
Table[Length[Select[Join@@Permutations/@allnorm[n],Length[qit[#]]===k&]],{n,5},{k,n}]
-
\\ here U(n,k) is A074650(n,k).
EulerMT(u)={my(n=#u, p=x*Ser(u), vars=variables(p)); Vec(exp( sum(i=1, n, substvec(p + O(x*x^(n\i)), vars, apply(v->v^i,vars))/i ))-1)}
U(n,k)={sumdiv(n, d, moebius(n/d) * k^d)/n}
A(n)={[Vecrev(p/y) | p<-sum(k=1, n, EulerMT(vector(n, n, y*U(n,k)))*sum(j=k, n, (-1)^(k-j)*binomial(j,k)))]}
{ my(T=A(10)); for(n=1, #T, print(T[n])) } \\ Andrew Howroyd, Dec 08 2018
Example and program corrected by
Gus Wiseman, Dec 08 2018
A254040
Number T(n,k) of primitive (= aperiodic) n-bead necklaces with colored beads of exactly k different colors; triangle T(n,k), n >= 0, 0 <= k <= n, read by rows.
Original entry on oeis.org
1, 0, 1, 0, 0, 1, 0, 0, 2, 2, 0, 0, 3, 9, 6, 0, 0, 6, 30, 48, 24, 0, 0, 9, 89, 260, 300, 120, 0, 0, 18, 258, 1200, 2400, 2160, 720, 0, 0, 30, 720, 5100, 15750, 23940, 17640, 5040, 0, 0, 56, 2016, 20720, 92680, 211680, 258720, 161280, 40320
Offset: 0
Triangle T(n,k) begins:
1;
0, 1;
0, 0, 1;
0, 0, 2, 2;
0, 0, 3, 9, 6;
0, 0, 6, 30, 48, 24;
0, 0, 9, 89, 260, 300, 120;
0, 0, 18, 258, 1200, 2400, 2160, 720;
0, 0, 30, 720, 5100, 15750, 23940, 17640, 5040;
...
The T(4,3) = 9 normal Lyndon words of length 4 with maximum 3 are: 1233, 1323, 1332, 1223, 1232, 1322, 1123, 1132, 1213. - _Gus Wiseman_, Dec 22 2017
Columns k=0-10 give:
A000007,
A063524,
A001037 (for n>1),
A056288,
A056289,
A056290,
A056291,
A254079,
A254080,
A254081,
A254082.
-
with(numtheory):
b:= proc(n, k) option remember; `if`(n=0, 1,
add(mobius(n/d)*k^d, d=divisors(n))/n)
end:
T:= (n, k)-> add(b(n, k-j)*binomial(k,j)*(-1)^j, j=0..k):
seq(seq(T(n, k), k=0..n), n=0..10);
-
b[n_, k_] := b[n, k] = If[n == 0, 1, Sum[MoebiusMu[n/d]*k^d, {d, Divisors[n]}]/n]; T[n_, k_] := Sum[b[n, k-j]*Binomial[k, j]*(-1)^j, {j, 0, k}]; Table[Table[T[n, k], {k, 0, n}], {n, 0, 10}] // Flatten (* Jean-François Alcover, Jan 27 2015, after Alois P. Heinz *)
LyndonQ[q_]:=q==={}||Array[OrderedQ[{q,RotateRight[q,#]}]&,Length[q]-1,1,And]&&Array[RotateRight[q,#]&,Length[q],1,UnsameQ];
allnorm[n_,k_]:=If[k===0,If[n===0,{{}}, {}],Join@@Permutations/@Function[s,Array[Count[s,y_/;y<=#]+1&,n]]/@Select[Subsets[Range[n-1]+1],Length[#]===k-1&]];
Table[Length[Select[allnorm[n,k],LyndonQ]],{n,0,7},{k,0,n}] (* Gus Wiseman, Dec 22 2017 *)
A281013
Tetrangle T(n,k,i) = i-th part of k-th prime composition of n.
Original entry on oeis.org
1, 2, 2, 1, 3, 2, 1, 1, 3, 1, 4, 2, 1, 1, 1, 2, 2, 1, 3, 1, 1, 3, 2, 4, 1, 5, 2, 1, 1, 1, 1, 2, 2, 1, 1, 3, 1, 1, 1, 3, 1, 2, 3, 2, 1, 4, 1, 1, 4, 2, 5, 1, 6, 2, 1, 1, 1, 1, 1, 2, 1, 2, 1, 1, 2, 2, 1, 1, 1, 2, 2, 2, 1, 3, 1, 1, 1, 1, 3, 1, 1, 2, 3, 1, 2, 1, 3, 2, 1, 1, 3, 2, 2, 3, 3, 1, 4, 1, 1, 1, 4, 1, 2, 4, 2, 1, 4, 3, 5, 1, 1, 5, 2, 6, 1, 7
Offset: 1
The prime factorization of (1, 1, 4, 2, 3, 1, 5, 5) is: (11423155) = (1)*(1)*(5)*(5)*(4231). The prime factorizations of the initial terms of A000002 are:
(1) = (1)
(12) = (1)*(2)
(122) = (1)*(2)*(2)
(1221) = (1)*(221)
(12211) = (1)*(2211)
(122112) = (1)*(2)*(2211)
(1221121) = (1)*(221121)
(12211212) = (1)*(2)*(221121)
(122112122) = (1)*(2)*(2)*(221121)
(1221121221) = (1)*(221)*(221121)
(12211212212) = (1)*(2)*(221)*(221121)
(122112122122) = (1)*(2)*(2)*(221)*(221121).
Read as a sequence:
(1), (2), (21), (3), (211), (31), (4), (2111), (221), (311), (32), (41), (5).
Read as a triangle:
(1)
(2)
(21), (3)
(211), (31), (4)
(2111), (221), (311), (32), (41), (5).
Read as a sequence of triangles:
1 2 2 1 2 1 1 2 1 1 1 2 1 1 1 1 2 1 1 1 1 1
3 3 1 2 2 1 2 2 1 1 2 1 2 1 1
4 3 1 1 3 1 1 1 2 2 1 1 1
3 2 3 1 2 2 2 2 1
4 1 3 2 1 3 1 1 1 1
5 4 1 1 3 1 1 2
4 2 3 1 2 1
5 1 3 2 1 1
6 3 2 2
3 3 1
4 1 1 1
4 1 2
4 2 1
4 3
5 1 1
5 2
6 1
7.
The binary non-"co" version is
A102659.
A sequence listing all Lyndon compositions is
A294859.
Numbers whose binary expansion is co-Lyndon are
A328596.
Numbers whose binary expansion is co-Lyndon are
A275692.
Cf.
A211097,
A211100,
A296372,
A296373,
A298941,
A329131,
A329312,
A329313,
A329314,
A329324,
A329326.
-
colynQ[q_]:=Array[Union[{RotateRight[q,#],q}]=={RotateRight[q,#],q}&,Length[q]-1,1,And];
lexsort[f_,c_]:=OrderedQ[PadRight[{f,c}]];
Table[Sort[Select[Join@@Permutations/@IntegerPartitions[n],colynQ],lexsort],{n,5}] (* Gus Wiseman, Nov 15 2019 *)
A294859
Triangle whose n-th row is the concatenated sequence of all Lyndon compositions of n in lexicographic order.
Original entry on oeis.org
1, 2, 1, 2, 3, 1, 1, 2, 1, 3, 4, 1, 1, 1, 2, 1, 1, 3, 1, 2, 2, 1, 4, 2, 3, 5, 1, 1, 1, 1, 2, 1, 1, 1, 3, 1, 1, 2, 2, 1, 1, 4, 1, 2, 3, 1, 3, 2, 1, 5, 2, 4, 6, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 3, 1, 1, 1, 2, 2, 1, 1, 1, 4, 1, 1, 2, 1, 2, 1, 1, 2, 3, 1, 1, 3, 2, 1
Offset: 1
Triangle of Lyndon compositions begins:
(1),
(2),
(12),(3),
(112),(13),(4),
(1112),(113),(122),(14),(23),(5),
(11112),(1113),(1122),(114),(123),(132),(15),(24),(6),
(111112),(11113),(11122),(1114),(11212),(1123),(1132),(115),(1213),(1222),(124),(133),(142),(16),(223),(25),(34),(7).
Cf.
A000740,
A001037,
A001045,
A008965,
A059966,
A060223,
A066099,
A101211,
A102659,
A124734,
A185700,
A228369,
A281013,
A296302,
A296373,
A296656.
-
LyndonQ[q_]:=Array[OrderedQ[{q,RotateRight[q,#]}]&,Length[q]-1,1,And]&&Array[RotateRight[q,#]&,Length[q],1,UnsameQ];
Table[Sort[Select[Join@@Permutations/@IntegerPartitions[n],LyndonQ],OrderedQ[PadRight[{#1,#2}]]&],{n,7}]
A296656
Triangle whose n-th row is the concatenated sequence of all Lyndon compositions of n in reverse-lexicographic order.
Original entry on oeis.org
1, 2, 3, 1, 2, 4, 1, 3, 1, 1, 2, 5, 2, 3, 1, 4, 1, 2, 2, 1, 1, 3, 1, 1, 1, 2, 6, 2, 4, 1, 5, 1, 3, 2, 1, 2, 3, 1, 1, 4, 1, 1, 2, 2, 1, 1, 1, 3, 1, 1, 1, 1, 2, 7, 3, 4, 2, 5, 2, 2, 3, 1, 6, 1, 4, 2, 1, 3, 3, 1, 2, 4, 1, 2, 2, 2, 1, 2, 1, 3, 1, 1, 5, 1, 1, 3, 2
Offset: 1
Triangle of Lyndon compositions begins:
(1),
(2),
(3),(12),
(4),(13),(112),
(5),(23),(14),(122),(113),(1112),
(6),(24),(15),(132),(123),(114),(1122),(1113),(11112),
(7),(34),(25),(223),(16),(142),(133),(124),(1222),(1213),(115),(1132),(1123),(11212),(1114),(11122),(11113),(111112).
Cf.
A000740,
A001037,
A001045,
A008965,
A059966,
A060223,
A066099,
A101211,
A102659,
A124734,
A185700,
A228369,
A281013,
A294859,
A296302,
A296373.
-
LyndonQ[q_]:=Array[OrderedQ[{q,RotateRight[q,#]}]&,Length[q]-1,1,And]&&Array[RotateRight[q,#]&,Length[q],1,UnsameQ];
Table[Sort[Select[Join@@Permutations/@IntegerPartitions[n],LyndonQ],OrderedQ[PadRight[{#2,#1}]]&],{n,7}]
A298971
Number of compositions of n that are proper powers of Lyndon words.
Original entry on oeis.org
0, 1, 1, 2, 1, 4, 1, 5, 3, 8, 1, 16, 1, 20, 9, 35, 1, 69, 1, 110, 21, 188, 1, 381, 7, 632, 59, 1184, 1, 2300, 1, 4115, 189, 7712, 25, 14939, 1, 27596, 633, 52517, 1, 101050, 1, 190748, 2247, 364724, 1, 703331, 19, 1342283, 7713, 2581430, 1, 4985609, 193
Offset: 1
The a(12) = 16 compositions: 111111111111, 1111211112, 11131113, 112112112, 11221122, 114114, 12121212, 123123, 131313, 132132, 1515, 222222, 2424, 3333, 444, 66.
Cf.
A000005,
A000031,
A000740,
A000961,
A001045,
A008965,
A019536,
A034691,
A051953,
A052823,
A059966,
A060223,
A178472,
A185700,
A296302,
A296373.
-
Table[Sum[DivisorSum[d,MoebiusMu[d/#]*(2^#-1)&]/d,{d,Most@Divisors[n]}],{n,100}]
-
a(n) = sumdiv(n, d, (2^d-1)*(eulerphi(n/d)-moebius(n/d))/n); \\ Michel Marcus, Jan 31 2018
A299023
Number of compositions of n whose standard factorization into Lyndon words has all strict compositions as factors.
Original entry on oeis.org
1, 2, 4, 7, 12, 23, 38, 66, 112, 193, 319, 539, 887, 1466, 2415, 3951, 6417, 10428, 16817, 27072, 43505, 69560, 110916, 176469, 279893, 442742, 698919, 1100898, 1729530, 2712134, 4244263, 6628174, 10332499, 16077835, 24972415, 38729239, 59958797, 92685287
Offset: 1
The a(5) = 12 compositions:
(5) = (5)
(41) = (4)*(1)
(14) = (14)
(32) = (3)*(2)
(23) = (23)
(311) = (3)*(1)*(1)
(131) = (13)*(1)
(221) = (2)*(2)*(1)
(212) = (2)*(12)
(2111) = (2)*(1)*(1)*(1)
(1211) = (12)*(1)*(1)
(11111) = (1)*(1)*(1)*(1)*(1)
Not included:
(113) = (113)
(122) = (122)
(1121) = (112)*(1)
(1112) = (1112)
Cf.
A001045,
A032020,
A032153,
A034691,
A049311,
A059966,
A089259,
A098407,
A116540,
A185700,
A270995,
A296373,
A299024,
A299026,
A299027.
-
nn=50;
ser=Product[1/(1-x^n)^Total[(Length[#]-1)!&/@Select[IntegerPartitions[n],UnsameQ@@#&]],{n,nn}];
Table[SeriesCoefficient[ser,{x,0,n}],{n,nn}]
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EulerT(v)={Vec(exp(x*Ser(dirmul(v,vector(#v,n,1/n))))-1, -#v)}
seq(N)={EulerT(Vec(sum(n=1, N-1, (n-1)!*x^(n*(n+1)/2)/prod(k=1, n, 1-x^k + O(x^N)))))} \\ Andrew Howroyd, Dec 01 2018
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