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 A111289 a(1) = a(2) = a(3) = a(4) = 1. For n>= 5, a(n) = a(n-1)*a(n-4) + a(n-2)*a(n-3). 0
 1, 1, 1, 1, 2, 3, 5, 11, 37, 166, 1237, 19749, 936055, 179814643, 240916863586, 4926183534613279, 4654499108310829164143, 838133896191338105830469104443, 201943518452400520392903690464302135967495, 994814736615560793049792416556718062880283217474796953454 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,5 LINKS PROG (PARI) a(n)=if(n<5, 1, a(n-1)*a(n-4) + a(n-2)*a(n-3)) (Klasen) CROSSREFS Sequence in context: A167604 A065510 A006721 * A255420 A127181 A323611 Adjacent sequences: A111286 A111287 A111288 * A111290 A111291 A111292 KEYWORD easy,nonn AUTHOR Leroy Quet, Nov 01 2005 EXTENSIONS More terms from Lambert Klasen (lambert.klasen(AT)gmx.net), Nov 06 2005 STATUS approved

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Last modified December 9 23:05 EST 2022. Contains 358710 sequences. (Running on oeis4.)