login
A051379
Generalized Stirling number triangle of first kind read by rows: T(n, k) = [x^k] Product_{m=1..n} (x - m - r), with r = 7.
17
1, -8, 1, 72, -17, 1, -720, 242, -27, 1, 7920, -3382, 539, -38, 1, -95040, 48504, -9850, 995, -50, 1, 1235520, -725592, 176554, -22785, 1645, -63, 1, -17297280, 11393808, -3197348, 495544, -45815, 2527, -77, 1, 259459200, -188204400, 59354028, -10630508, 1182769, -83720, 3682, -92, 1
OFFSET
0,2
COMMENTS
T(n, m) = ^8P_n^m in the notation of the given reference with T(0, 0) = 1.
The monic row polynomials s(n, x) = Sum_{m=0..n} T(n, m)*x^m which are s(n, x) = Product_{k=0..n-1} x-(8+k), n >= 1 and s(0, x) = 1 satisfy s(n, x+y) = Sum_{k=0..n} binomial(n, k)*s(k, x)*S1(n-k, y), with the Stirling1 polynomials S1(n, x) = Sum_{m=1..n} A008275(n, m)*x^m and S1(0, x) = 1. In the umbral calculus (see the S. Roman reference given in A048854) the s(n, x) polynomials are called Sheffer for (exp(8*t), exp(t)-1).
LINKS
Dragoslav S. Mitrinović and Ružica S. Mitrinović, Tableaux d'une classe de nombres reliés aux nombres de Stirling, Univ. Beograd. Pubi. Elektrotehn. Fak. Ser. Mat. Fiz. 77 (1962); alternative link.
FORMULA
T(n, m) = T(n-1, m-1) - (n+7)*T(n-1, m), n >= m >= 0; T(n, m) = 0, n < m; T(n, -1) = 0, T(0, 0) = 1.
E.g.f. for m-th column of signed triangle: ((log(1+x))^m)/(m!*(1+x)^8).
Triangle (signed) = [ -8, -1, -9, -2, -10, -3, -11, -4, -12, ...] DELTA A000035; triangle (unsigned) = [8, 1, 9, 2, 10, 3, 11, 4, 12, 5, ...] DELTA A000035; where DELTA is Deléham's operator defined in A084938.
If we define f(n, i, a) = Sum_{k=0..n-i} binomial(n,k)*stirling1(n-k,i)*Product_{j=0..k-1}(-a-j), then T(n, i) = f(n, i, 8), for n=1,2,...; i=0..n. - Milan Janjic, Dec 21 2008
EXAMPLE
Triangle begins:
1;
-8, 1;
72, -17, 1;
-720, 242, -27, 1;
...
s(2, x)=72-17*x+x^2; S1(2, x)= -x+x^2 (Stirling1).
MATHEMATICA
a[n_, m_] := Pochhammer[m + 1, n - m] SeriesCoefficient[Log[1 + x]^m/(1 + x)^8, {x, 0, n}];
Table[a[n, m], {n, 0, 8}, {m, 0, n}] // Flatten (* Jean-François Alcover, Oct 29 2019 *)
PROG
(Haskell)
a051379 n k = a051379_tabl !! n !! k
a051379_row n = a051379_tabl !! n
a051379_tabl = map fst $ iterate (\(row, i) ->
(zipWith (-) ([0] ++ row) $ map (* i) (row ++ [0]), i + 1)) ([1], 8)
-- Reinhard Zumkeller, Mar 12 2014
CROSSREFS
The first (m=0) column sequence is: A049388. Row sums (signed triangle): A001730(n+6)*(-1)^n. Row sums (unsigned triangle): A049389(n).
Similar generalizations: A049444 (r=1), A049458 (r=2), A049459 (r=3), A049460 (r=4), A051338 (r=5), A051339 (r=6), A051390 (r=8), A051523 (r=9).
Sequence in context: A075503 A260040 A380860 * A143499 A114152 A347111
KEYWORD
sign,easy,tabl
EXTENSIONS
Typo fixed in data by Reinhard Zumkeller, Mar 12 2014
Name changed by Thomas Scheuerle, Feb 04 2026
STATUS
approved