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A001904 From higher order Bernoulli numbers: absolute value of numerator of D Number D2n(2n).
(Formerly M2178 N0871)
3
1, 2, 88, 3056, 319616, 18940160, 94645408768, 526713485312, 2012969145761792, 1516106277997969408, 950096677725742563328, 125099579935028774699008, 1308695886352702185064628224, 7547869395875499805522264064 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
COMMENTS
Also, absolute values of reduced numerators of D-Noerlund numbers. By the way, Table 11 from the Nørlund reference (p. 462) gives correctly the first 6 reduced numerators of the D-Noerlund numbers but in the 7th one the author makes a mistake and doesn't divide the numerator (283936226304) and the corresponding denominator (4095) by their common factor (3) to obtain the reduced fraction: 94645408768/1365 which gives the correct value for a(6): 94645408768. - Herman Jamke (hermanjamke(AT)fastmail.fm), Jul 26 2010
REFERENCES
N. E. Nørlund, Vorlesungen über Differenzenrechnung. Springer-Verlag, Berlin, 1924, p. 462.
N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
Guodong Liu, A Recurrence Formula for D Numbers D2n(2n-1), Discrete Dynamics in Nature and Society, Volume 2009 (2009). [From Herman Jamke (hermanjamke(AT)fastmail.fm), Jul 26 2010]
N. E. Nørlund, Vorlesungen über Differenzenrechnung Springer 1924, p. 462.
N. E. Nørlund, Vorlesungen über Differenzenrechnung Springer 1924, p. 462.
N. E. Nörlund, Vorlesungen über Differenzenrechnung, Springer-Verlag, Berlin, 1924; page 462 [Annotated scanned copy of pages 144-151 and 456-463]
FORMULA
E.g.f. for D-Noerlund numbers: (x/log(x+sqrt(1+x^2)))/sqrt(1+x^2). - Herman Jamke (hermanjamke(AT)fastmail.fm), Jul 26 2010
EXAMPLE
From Herman Jamke (hermanjamke(AT)fastmail.fm), Jul 26 2010: (Start)
For n=0 the D-Noerlund number is 1 so a(0)=1.
For n=1 the D-Noerlund number is -2/3 so a(1)=2.
For n=2 the D-Noerlund number is 88/15 so a(2)=88.
For n=3 the D-Noerlund number is -3056/21 so a(3)=3056.
For n=4 the D-Noerlund number is 319616/45 so a(4)=319616.
For n=5 the D-Noerlund number is -18940160/33 so a(5)=18940160.
For n=6 the D-Noerlund number is 94645408768/1365 so a(6)=94645408768, ... .
(End)
MAPLE
seq(abs(numer(coeff(convert(series((t/log(t+sqrt(1+t^2)))/sqrt(1+t^2), t, 50), polynom), t, 2*n)*(2*n)!)), n=0..23); # Herman Jamke (hermanjamke(AT)fastmail.fm), Jul 26 2010
MATHEMATICA
NorlundD[nu_, n_] := (-2)^nu NorlundB[nu, n, n/2];
Table[NorlundD[2 n, 2 n] // Numerator // Abs, {n, 0, 13}] (* Jean-François Alcover, Jul 02 2019 *)
PROG
(PARI)
x='x + O('x^28);
abs(apply(numerator, select(i->i, Vec(serlaplace((x / log(x + sqrt(1+x^2))) / sqrt(1+x^2)))))) \\ Gheorghe Coserea, Aug 24 2015
CROSSREFS
Cf. A001905, A261272, A261274 (denominator).
Sequence in context: A364974 A166848 A283631 * A053950 A266182 A362519
KEYWORD
nonn,frac
AUTHOR
EXTENSIONS
Corrected and extended by Herman Jamke (hermanjamke(AT)fastmail.fm), Jul 26 2010
STATUS
approved

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Last modified April 25 06:42 EDT 2024. Contains 371964 sequences. (Running on oeis4.)