|
|
A000175
|
|
Related to zeros of Bessel function.
(Formerly M2000 N0790)
|
|
3
|
|
|
1, 1, 2, 11, 38, 946, 4580, 202738, 3786092, 261868876, 1992367192, 2381255244240, 21411255538848, 2902625722978656, 451716954504285504, 319933105641374465472, 3761845343198709705600
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,3
|
|
COMMENTS
|
Constant term of the Rayleigh polynomials. [From Herman Jamke (hermanjamke(AT)fastmail.fm), Aug 20 2010]
|
|
REFERENCES
|
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
|
N. Kishore, The Rayleigh Polynomial, Proc. Amer. Math. Soc. 15, No. 6 (1964), pp. 911-917. [From Herman Jamke (hermanjamke(AT)fastmail.fm), Aug 20 2010]
|
|
MATHEMATICA
|
pi0[n_] := Product[k^Floor[n/k], {k, 1, n}]; J[v_, m_] := Sum[(-1)^n*(x/2)^( 2*n + v)/(n!*(n+v)!), {n, 0, m}] + O[x]^(2*m+v); p = J[1, 101]/(2*J[0, 101]); Reap[For[n=1, n <= 40, n += 2, Print["a(", (n+1)/2, ") = ", an = SeriesCoefficient[p, n]*pi0[(n+1)/2]*2^(n+1)]; Sow[an]]][[2, 1]] (* Jean-François Alcover, Feb 04 2016, adapted from Herman Jamke's 2nd PARI script *)
|
|
PROG
|
(PARI) alpha(k, n)=if(k<floor(n/2), 2, if(n%2==1, 2, 1))
e(r, k, n)=floor(n/r)-floor(k/r)-floor((n-k)/r)
phi2(n)=if(n<3, return(1), return(sum(k=1, floor(n/2), alpha(k, n)*phi2(k)*phi2(n-k)*prod(r=1, n-1, (v+r)^e(r, k, n)))))
for(m=1, 30, print1(polcoeff(phi2(m), 0)", ")) \\ Herman Jamke (hermanjamke(AT)fastmail.fm), Aug 20 2010
(PARI) pi0(n)=prod(k=1, n, k^floor(n/k))
J(v, m)=sum(n=0, m, (-1)^n*(x/2)^(2*n+v)/(n!*(n+v)!))+O(x^(2*m+v))
p=J(1, 101)/(2*J(0, 101)); forstep(n=1, 200, 2, print((n+1)/2" "polcoeff(p, n)*pi0((n+1)/2)*2^(n+1))) \\ Herman Jamke (hermanjamke(AT)fastmail.fm), Sep 03 2010
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
EXTENSIONS
|
More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Aug 20 2010
|
|
STATUS
|
approved
|
|
|
|