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A141587
Nonprimes of the form c(c(c(i)-3)-3)-3, where A002808(i)=c(i)=i-th composite.
0
1, 24, 25, 27, 33, 35, 42, 45, 46, 48, 51, 55, 57, 62, 65, 66, 69, 72, 74, 77, 82, 84, 87, 88, 91, 93, 95, 96, 102, 105, 108, 111, 112, 115, 116, 117, 119, 121, 123, 125, 126, 129, 132, 133, 140, 141, 143, 144, 145, 150, 152, 153, 155, 156, 158, 161, 162, 166, 168
OFFSET
1,2
EXAMPLE
If i=1, then
c(c(c(1)-3)-3)-3=c(c(4-3)-3)-3=c(4-3)-3==4-3=1=a(1).
If i=7, then
c(c(c(7)-3)-3)-3=c(c(14-3)-3)-3=c(20-3)-3=27-3=24=a(2).
If i=8, then
c(c(c(8)-3)-3)-3=c(c(15-3)-3)-3=c(21-3)-3=28-3=25=a(3).
If i=9, then
c(c(c(9)-3)-3)-3=c(c(16-3)-3)-3=c(22-3)-3=30-3=27=a(4).
If i=11, then
c(c(c(11)-3)-3)-3=c(c(20-3)-3)-3=c(27-3)-3=36-3=33=a(5),
etc.
CROSSREFS
Cf. A002808.
Sequence in context: A167458 A066024 A123608 * A296866 A241890 A027729
KEYWORD
nonn
AUTHOR
EXTENSIONS
78 removed by R. J. Mathar, Sep 05 2008
STATUS
approved