login
A115033
Alternately multiply and divide, with a(1)=2 and a(2)=3.
3
2, 3, 6, 2, 12, 6, 72, 12, 864, 72, 62208, 864, 53747712, 62208, 3343537668096, 53747712, 17970749926243172352, 334353766096, 60108447043798927317622177792, 179774996243172352
OFFSET
1,1
FORMULA
a(2*k) = a(2*k-3); a(2*k+1) = a(2*k)*a(2*k-1) - Georg Fischer, Jun 18 2021
MAPLE
addmul:=proc(k, m, maxn): local f:
f:= proc(n) if n::even
then k^combinat:-fibonacci(n/2-1) *m^combinat:-fibonacci(n/2-2)
else k^combinat:-fibonacci((n+1)/2)*m^combinat:-fibonacci((n-1)/2)
fi
end proc:
map(f, [$1..maxn]);
end proc: # after Robert Israel in A174348
addmul(2, 3, 20); # Georg Fischer, Jun 18 2021
MATHEMATICA
nxt[{a_, b_}]:={a*b, (a*b)/b}; NestList[nxt, {2, 3}, 10]//Flatten (* Georg Fischer, Jun 18 2021 *)
CROSSREFS
Sequence in context: A275666 A330666 A319432 * A214630 A093396 A189971
KEYWORD
easy,nonn
AUTHOR
Giovanni Teofilatto, Feb 26 2006
EXTENSIONS
Definition adapted to offset by Georg Fischer, Jun 18 2021
STATUS
approved