|
Search: id:A065100
|
|
|
| A065100 |
|
a(0) = c, a(1) = p*c^3; a(n+2) = p*c^2*a(n+1) - a(n), for p = 1, c = 3. |
|
+0
1
|
|
| 3, 27, 240, 2133, 18957, 168480, 1497363, 13307787, 118272720, 1051146693, 9342047517, 83027280960, 737903481123, 6558104049147, 58285032961200, 518007192601653, 4603779700453677, 40916010111481440, 363640311302879283
(list; graph; listen)
|
|
|
OFFSET
|
0,1
|
|
|
LINKS
|
Tanya Khovanova, Recursive Sequences
J.-P. Ehrmann et al., Problem POLYA002, Integer pairs (x,y) for which (x^2+y^2)/(1+pxy) is an integer.
|
|
FORMULA
|
G.f.: 3/(1-9*x+x^2).
|
|
MATHEMATICA
|
a[0] = c; a[1] = p*c^3; a[n_] := a[n] = p*c^2*a[n - 1] - a[n - 2]; p = 1; c = 3; Table[ a[n], {n, 0, 20} ]
|
|
PROGRAM
|
(PARI): polya002(1, 3, 20). For definition of function polya002 see A052530.
|
|
CROSSREFS
|
Cf. A052530.
Sequence in context: A043023 A087426 A083713 this_sequence A035088 A013708 A102518
Adjacent sequences: A065097 A065098 A065099 this_sequence A065101 A065102 A065103
|
|
KEYWORD
|
easy,nonn
|
|
AUTHOR
|
njas, Nov 12 2001
|
|
EXTENSIONS
|
More terms from Marc LeBrun (mlb(AT)well.com) and Robert G. Wilson v (rgwv(AT)rgwv.com), Nov 12 2001
Gen. func. from Floor van Lamoen (fvlamoen(AT)hotmail.com), Feb 07 2002
|
|
|
Search completed in 0.002 seconds
|
