A111492
Triangle read by rows: a(n,k) = (k-1)! * C(n,k).
Original entry on oeis.org
1, 2, 1, 3, 3, 2, 4, 6, 8, 6, 5, 10, 20, 30, 24, 6, 15, 40, 90, 144, 120, 7, 21, 70, 210, 504, 840, 720, 8, 28, 112, 420, 1344, 3360, 5760, 5040, 9, 36, 168, 756, 3024, 10080, 25920, 45360, 40320, 10, 45, 240, 1260, 6048, 25200, 86400, 226800, 403200, 362880
Offset: 1
a(3,3) = 2 because (3-1)!C(3,3) = 2.
1;
2 1;
3 3 2;
4 6 8 6;
5 10 20 30 24;
6 15 40 90 144 120;
7 21 70 210 504 840 720;
8 28 112 420 1344 3360 5760 5040;
9 36 168 756 3024 10080 25920 45360 40320;
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/* As triangle: */ [[Factorial(k-1)*Binomial(n,k): k in [1..n]]: n in [1.. 15]]; // Vincenzo Librandi, Oct 21 2014
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Flatten[Table[(k - 1)!Binomial[n, k], {n, 10}, {k, n}]]
A045501
Third-from-right diagonal of triangle A121207.
Original entry on oeis.org
1, 1, 4, 14, 54, 233, 1101, 5625, 30846, 180474, 1120666, 7352471, 50772653, 367819093, 2787354668, 22039186530, 181408823710, 1551307538185, 13756835638385, 126298933271289, 1198630386463990, 11742905240821910
Offset: 1
-
a[1] = a[2] = 1; a[n_] := a[n] = Sum[Binomial[n, k+1]*a[k], {k, 0, n-1}];
Array[a, 22] (* Jean-François Alcover, Jul 14 2018, after Vladeta Jovovic *)
-
{a(n)=local(A=x+x^2); for(i=1, n, A=x+x*subst(A, x, x/(1-x+x*O(x^n)))/(1-x)^2); polcoeff(A, n)} /* Paul D. Hanna, Mar 23 2012 */
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# The function Gould_diag is defined in A121207.
A045501_list = lambda size: Gould_diag(3, size)
print(A045501_list(24)) # Peter Luschny, Apr 24 2016
A014831
a(1)=1; for n>1, a(n) = 8*a(n-1) + n.
Original entry on oeis.org
1, 10, 83, 668, 5349, 42798, 342391, 2739136, 21913097, 175304786, 1402438299, 11219506404, 89756051245, 718048409974, 5744387279807, 45955098238472, 367640785907793, 2941126287262362, 23529010298098915, 188232082384791340, 1505856659078330741, 12046853272626645950
Offset: 1
For n=5, a(5) = 1*15 + 7*20 + 7^2*15 + 7^3*6 + 7^4*1 = 5349. [_Bruno Berselli_, Nov 13 2015]
- Colin Barker, Table of n, a(n) for n = 1..1000
- Dillan Agrawal, Selena Ge, Jate Greene, Tanya Khovanova, Dohun Kim, Rajarshi Mandal, Tanish Parida, Anirudh Pulugurtha, Gordon Redwine, Soham Samanta, and Albert Xu, Chip-Firing on Infinite k-ary Trees, arXiv:2501.06675 [math.CO], 2025. See p. 18.
- Index entries for linear recurrences with constant coefficients, signature (10,-17,8).
-
a:=n->sum((8^(n-j)-1)/7,j=0..n): seq(a(n), n=1..19); # Zerinvary Lajos, Jan 15 2007
a:= n-> (Matrix ([[1, 0, 1], [1, 1, 1], [0, 0, 8]])^n)[2, 3]: seq (a(n), n=1..25); # Alois P. Heinz, Aug 06 2008
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Table[(8^(n + 1) - 7 n - 8)/49, {n, 1, 25}] (* Bruno Berselli, Nov 13 2015 *)
nxt[{n_,a_}]:={n+1,8a+n+1}; NestList[nxt,{1,1},30][[;;,2]] (* Harvey P. Dale, Aug 09 2025 *)
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Vec(x/((1 - x)^2*(1 - 8*x)) + O(x^25)) \\ Colin Barker, Jun 03 2020
A014830
a(1)=1; for n > 1, a(n) = 7*a(n-1) + n.
Original entry on oeis.org
1, 9, 66, 466, 3267, 22875, 160132, 1120932, 7846533, 54925741, 384480198, 2691361398, 18839529799, 131876708607, 923136960264, 6461958721864, 45233711053065, 316635977371473, 2216451841600330, 15515162891202330, 108606140238416331, 760242981668914339, 5321700871682400396
Offset: 1
For n=5, a(5) = 1*15 + 6*20 + 6^2*15 + 6^3*6 + 6^4*1 = 3267. - _Bruno Berselli_, Nov 13 2015
- Colin Barker, Table of n, a(n) for n = 1..1000
- Dillan Agrawal, Selena Ge, Jate Greene, Tanya Khovanova, Dohun Kim, Rajarshi Mandal, Tanish Parida, Anirudh Pulugurtha, Gordon Redwine, Soham Samanta, and Albert Xu, Chip-Firing on Infinite k-ary Trees, arXiv:2501.06675 [math.CO], 2025. See p. 18.
- Index entries for linear recurrences with constant coefficients, signature (9,-15,7).
-
a:=n->sum((7^(n-j)-1)/6,j=0..n): seq(a(n), n=1..19); # Zerinvary Lajos, Jan 15 2007
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a[1] = 1; a[n_] := 7*a[n-1]+n; Table[a[n], {n, 10}] (* Zak Seidov, Feb 06 2011 *)
LinearRecurrence[{9, -15, 7}, {1, 9, 66}, 30] (* Harvey P. Dale, Jul 22 2013 *)
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Vec(x/((1 - x)^2*(1 - 7*x)) + O(x^25)) \\ Colin Barker, Jun 03 2020
A014832
a(1)=1; for n>1, a(n) = 9*a(n-1) + n.
Original entry on oeis.org
1, 11, 102, 922, 8303, 74733, 672604, 6053444, 54481005, 490329055, 4412961506, 39716653566, 357449882107, 3217048938977, 28953440450808, 260580964057288, 2345228676515609, 21107058088640499, 189963522797764510, 1709671705179880610, 15387045346618925511, 138483408119570329621
Offset: 1
For n=5, a(5) = 1*15 + 8*20 + 8^2*15 + 8^3*6 + 8^4*1 = 8303. [_Bruno Berselli_, Nov 13 2015]
- Seiichi Manyama, Table of n, a(n) for n = 1..1000
- Dillan Agrawal, Selena Ge, Jate Greene, Tanya Khovanova, Dohun Kim, Rajarshi Mandal, Tanish Parida, Anirudh Pulugurtha, Gordon Redwine, Soham Samanta, and Albert Xu, Chip-Firing on Infinite k-ary Trees, arXiv:2501.06675 [math.CO], 2025. See p. 18.
- Index entries for linear recurrences with constant coefficients, signature (11,-19,9).
-
a:=n->sum((9^(n-j)-1)/8,j=0..n): seq(a(n), n=1..18); # Zerinvary Lajos, Jan 15 2007
a:= n-> (Matrix([[1,0,1],[1,1,1],[0,0,9]])^n)[2,3]: seq(a(n), n=1..18); # Alois P. Heinz, Aug 06 2008
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RecurrenceTable[{a[1]==1,a[n]==9a[n-1]+n},a,{n,20}] (* or *) LinearRecurrence[ {11,-19,9},{1,11,102},20] (* Harvey P. Dale, May 01 2012 *)
A126277
Triangle generated from Eulerian numbers.
Original entry on oeis.org
1, 1, 2, 1, 3, 3, 1, 4, 7, 4, 1, 5, 11, 15, 5, 1, 6, 15, 26, 31, 6, 1, 7, 19, 37, 57, 63, 7, 1, 8, 23, 48, 83, 120, 127, 8, 1, 9, 27, 59, 109, 177, 247, 255, 9, 1, 10, 31, 70, 135, 234, 367, 502, 511, 10
Offset: 1
First few rows of the triangle:
1;
1, 2;
1, 3, 3;
1, 4, 7, 4;
1, 5, 11, 15, 5;
1, 6, 15, 26, 31, 6;
1, 7, 19, 37, 57, 63, 7;
1, 8, 23, 48, 83, 120, 127, 8;
1, 9, 27, 59, 109, 177, 247, 255, 9;
1, 10, 31, 70, 135, 234, 367, 502, 511, 10;
...
T(7,4) = 37 = A000295(4) + T(6,4) = 11 + 26.
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T[n_,1]:=1; T[n_,n_]:=n; T[n_,k_]:= T[n-1,k] + 2^k - k - 1; Table[T[n,k], {n,1,15}, {k,1,n}]//Flatten (* G. C. Greubel, Oct 23 2018 *)
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{T(n,k) = if(k==1, 1, if(k==n, n, 2^k - k - 1 + T(n-1,k)))};
for(n=1,10, for(k=1,n, print1(T(n,k), ", "))) \\ G. C. Greubel, Oct 23 2018
A243662
Triangle read by rows: the reversed x = 1+q Narayana triangle at m=2.
Original entry on oeis.org
1, 3, 1, 12, 8, 1, 55, 55, 15, 1, 273, 364, 156, 24, 1, 1428, 2380, 1400, 350, 35, 1, 7752, 15504, 11628, 4080, 680, 48, 1, 43263, 100947, 92169, 41895, 9975, 1197, 63, 1, 246675, 657800, 708400, 396704, 123970, 21560, 1960, 80, 1, 1430715, 4292145, 5328180, 3552120, 1381380, 318780, 42504, 3036, 99, 1
Offset: 1
Triangle begins:
1;
3, 1;
12, 8, 1;
55, 55, 15, 1;
273, 364, 156, 24, 1;
1428, 2380, 1400, 350, 35, 1;
...
- Michael De Vlieger, Table of n, a(n) for n = 1..11325 (rows 1 <= n <= 150, flattened)
- Paul Barry, On the inversion of Riordan arrays, arXiv:2101.06713 [math.CO], 2021.
- J.-C. Novelli and J.-Y. Thibon, Hopf Algebras of m-permutations,(m+1)-ary trees, and m-parking functions, arXiv preprint arXiv:1403.5962 [math.CO], 2014. See Fig. 10.
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T[m_][n_, k_] := Binomial[(m + 1) n + 1 - k, n - k] Binomial[n, k - 1]/n;
Table[T[2][n, k], {n, 1, 10}, {k, 1, n}] // Flatten (* Jean-François Alcover, Feb 12 2019 *)
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T(n)=[Vecrev(p) | p<-Vec(serreverse(x/((1+x+x*y)*(1+x)^2) + O(x*x^n)))]
{ my(A=T(10)); for(i=1, #A, print(A[i])) } \\ Andrew Howroyd, Apr 13 2023
Data and Example (T(2,2) and T(5,3)) corrected and more terms added by
Werner Schulte, Nov 22 2018
A104713
Triangle T(n,k) = binomial(n,k), read by rows, 3 <= k <=n .
Original entry on oeis.org
1, 4, 1, 10, 5, 1, 20, 15, 6, 1, 35, 35, 21, 7, 1, 56, 70, 56, 28, 8, 1, 84, 126, 126, 84, 36, 9, 1, 120, 210, 252, 210, 120, 45, 10, 1, 165, 330, 462, 462, 330, 165, 55, 11, 1, 220, 495, 792, 924, 792, 495, 220, 66, 12, 1, 286, 715, 1287, 1716
Offset: 3
First few rows of the triangle are:
1;
4, 1;
10, 5, 1;
20, 15, 6, 1;
35, 35, 21, 7, 1;
56, 70, 56, 28, 8, 1;
...
A380851
Riordan array ((1-x)^(m-1), x/(1-x)) with factor r^(2*n) on row n, for m = 3/2, r = 2.
Original entry on oeis.org
1, -2, 4, -2, 8, 16, -4, 24, 96, 64, -10, 80, 480, 640, 256, -28, 280, 2240, 4480, 3584, 1024, -84, 1008, 10080, 26880, 32256, 18432, 4096, -264, 3696, 44352, 147840, 236544, 202752, 90112, 16384, -858, 13728, 192192, 768768, 1537536, 1757184, 1171456, 425984, 65536
Offset: 0
Triangle starts:
k = 0 1 2 3 4 5 6
n=0: 1;
n=1: -2, 4;
n=2: -2, 8, 16;
n=3: -4, 24, 96, 64;
n=4: -10, 80, 480, 640, 256;
n=5: -28, 280, 2240, 4480, 3584, 1024;
n=6: -84, 1008, 10080, 26880, 32256, 18432, 4096;
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T:=(m,r,n,k)->add(binomial(i+m,m)*binomial(n+1,n-k-i)*r^(2*n)*(-1)^(i),i=0..n-k): m:=3/2: r:=2: seq(print(seq(T(m,r,n,k), k=0..n)), n=0..10);
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T[n_, k_] := 4^n Binomial[n, k] Hypergeometric2F1[3/2, k - n, k + 1, 1];
Table[T[n, k], {n, 0, 8}, {k, 0, n}] // Flatten (* Peter Luschny, Feb 07 2025 *)
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# Using function riordan_array from A256893.
RA = riordan_array((1 - x)^(3/2 - 1), x/(1-x), 7)
for n in range(7): print(4^n * RA.row(n)[:n+1]) # Peter Luschny, Feb 28 2025
A168577
Pascal's triangle, first two columns and diagonal removed.
Original entry on oeis.org
3, 6, 4, 10, 10, 5, 15, 20, 15, 6, 21, 35, 35, 21, 7, 28, 56, 70, 56, 28, 8, 36, 84, 126, 126, 84, 36, 9, 45, 120, 210, 252, 210, 120, 45, 10, 55, 165, 330, 462, 462, 330, 165, 55, 11, 66, 220, 495, 792, 924, 792, 495, 220, 66, 12, 78, 286, 715, 1287, 1716, 1716, 1287
Offset: 2
3;
6, 4;
10, 10, 5;
15, 20, 15, 6;
21, 35, 35, 21, 7;
28, 56, 70, 56, 28, 8;
36, 84, 126, 126, 84, 36, 9;
45, 120, 210, 252, 210, 120, 45, 10;
55, 165, 330, 462, 462, 330, 165, 55, 11;
66, 220, 495, 792, 924, 792, 495, 220, 66, 12;
78, 286, 715, 1287, 1716, 1716, 1287, 715, 286, 78, 13;
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p[x_, n_] = ((x + 1)^n - x^n - n*x - 1)/x^2;
Table[CoefficientList[p[x, n], x], {n, 3, 13}];
Flatten[%]
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