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A287635
a(1) = a(2) = a(3) = a(4) = 1; a(n) = a(a(n-4)) + a(n-a(n-3)) for n > 4.
1
1, 1, 1, 1, 2, 3, 4, 4, 4, 4, 5, 5, 5, 5, 6, 7, 7, 7, 8, 9, 9, 9, 9, 10, 11, 11, 11, 11, 12, 13, 14, 14, 14, 14, 14, 14, 14, 15, 16, 16, 16, 17, 18, 18, 18, 18, 19, 20, 21, 21, 22, 23, 23, 23, 23, 23, 23, 23, 23, 23, 24, 25, 25, 25, 26, 27, 28, 28, 28, 28, 29, 29, 29, 29, 30, 31, 32, 32
OFFSET
1,5
MAPLE
a:= proc(n) option remember: if n<5 then 1 else procname(procname(n-4))+procname(n-procname(n-3)) fi end: seq(a(n), n=1..80); # Muniru A Asiru, Jun 06 2018
PROG
(PARI) q=vector(100000); q[1]=q[2]=q[3]=q[4]=1; for(n=5, #q, q[n]=q[q[n-4]]+q[n-q[n-3]]); vector(100000, n, q[n])
(GAP) a:=[1, 1, 1, 1];; for n in [5..80] do a[n]:=a[a[n-4]]+a[n-a[n-3]]; od; a; # Muniru A Asiru, Jun 06 2018
CROSSREFS
Sequence in context: A308411 A087848 A087844 * A189660 A194167 A140427
KEYWORD
nonn,look
AUTHOR
Altug Alkan, May 28 2017
STATUS
approved