A309006 Product minus sum of the two previous terms in the sequence, with a(1) = 2 and a(2) = 5.

2, 5, 3, 7, 11, 59, 579, 33523, 19375715, 649512684707, 12584772018235630083, 8173969059977170083865314925891, 102867537103924486790122812065087346778963284622979

Offset

1,1

Links

Christopher C. Capobianco, Table of n, a(n) for n = 1..18

Formula

a(n) = a(n-1)*a(n-2) - (a(n-1)+a(n-2)), with a(1) = 2, a(2) = 5.

Example

a(3) = a(1) * a(2) - (a(1) + a(2)) = 2 * 5 - (2 + 5) = 3.

Mathematica

RecurrenceTable[{x[n+1]==x[n]*x[n-1]-(x[n]+x[n-1]), x[1]==2, x[2]==5}, x, {n, 1, 18}]

Prog

(Magma) I:=[2, 5]; [n le 2 select I[n] else Self(n-1)*Self(n-2)-(Self(n-1)+Self(n-2)): n in [1..14]]; // Vincenzo Librandi, Jul 10 2019

Crossrefs

Cf. A173096, A268021.

Sequence in context: A083190 A171026 A064359 * A082152 A354688 A084334

Adjacent sequences: A309003 A309004 A309005 * A309007 A309008 A309009

Keyword

nonn

Author

Christopher C. Capobianco, Jul 05 2019

Status

approved