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A087850
a(n) = a(a(a(a(a(n-1))))) + abs(2*a(n-1)-n).
0
1, 1, 2, 1, 4, 3, 2, 5, 2, 7, 4, 5, 4, 7, 2, 13, 10, 3, 14, 9, 4, 15, 8, 9, 8, 11, 6, 17, 6, 19, 8, 17, 2, 31, 28, 22, 8, 23, 8, 25, 10, 23, 4, 37, 30, 16, 16, 17, 16, 19, 14, 25, 4, 47, 40, 28, 3, 53, 48, 38, 19, 25, 14, 37, 10, 47, 28, 14, 42, 18, 36, 1, 72, 71, 69, 67, 64, 54, 33, 15
OFFSET
1,3
COMMENTS
Undefined for k >= 170. - Hugo Pfoertner, Dec 18 2022
PROG
(True BASIC)
70 DIM q0(0 to 4000)
80 LET q0(1)=1
90 LET q0(2)=1
91 FOR n = 3 to 176
92 LET q0(n)=q0(q0(q0(q0(q0(n-1)))))+Abs(2*q0(n-1)-n)
93 NEXT n
100 SET MODE "color"
110 SET WINDOW 0, 1024, 0, 750 301 PRINT" penta sequence" 302 PRINT" by Roger L. Bagula Oct 07 2003 "
381 OPEN #1: name "CM1:penta_data", create newold, org text
390 FOR x=1 to 176 391 PRINT #1: q0(x); ", ";
392 PRINT q0(x);
393 NEXT x
394 CLOSE #1
460 END
CROSSREFS
Sequence in context: A103122 A214918 A328394 * A087849 A075015 A205558
KEYWORD
nonn,less,fini
AUTHOR
Roger L. Bagula, Oct 08 2003
STATUS
approved