|
Search: id:A090212
|
|
| |
|
| 1, -4, 73, -3241, 223546, -10884061, -5437091357, 4560715140638, -2741631069546683, 1315509914960956853, -135771066929217673256, -969783690708328561039261, 1943740128890758048004419957, -2140191682145533094039398047820
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
REFERENCES
|
P. Blasiak, K. A. Penson and A. I. Solomon, The general boson normal ordering problem, Phys. Lett. A 309 (2003) 198-205.
M. Schork, On the combinatorics of normal ordering bosonic operators and deforming it, J. Phys. A 36 (2003) 4651-4665.
|
|
LINKS
|
P. Blasiak, K. A. Penson and A. I. Solomon, The general boson normal ordering problem.
|
|
FORMULA
|
a(n) := sum( A078741(n, k)*(-1)^(k+1), k=3..3*n), n>=1. a(0) := -1 may be added.
a(n) = -sum(((-1)^k)*(fallfac(k, 3)^n)/k!, k=3..infinity)*exp(1), with fallfac(k, 3)=A008279(k, 3)=k*(k-1)*(k-2) and n>=1. This produces also a(0)=-1.
E.g.f. if a(0)=-1 is added: -exp(1)*(sum(((-1)^k)*exp(fallfac(k, 3)*x)/k!, k=3..infinity)+1/2). Similar to derivation on top of p. 4656 of the Schork reference.
|
|
CROSSREFS
|
Cf. A000587, A090211. A069223 (non-alternating sum, generalized Bell-numbers).
Sequence in context: A055556 A089665 A092871 this_sequence A137046 A104335 A156494
Adjacent sequences: A090209 A090210 A090211 this_sequence A090213 A090214 A090215
|
|
KEYWORD
|
sign,easy
|
|
AUTHOR
|
Wolfdieter Lang (wolfdieter.lang_AT_physik_DOT_uni-karlsruhe_DOT_de), Dec 01 2003
|
|
|
Search completed in 0.003 seconds
|
