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A102258
Begin with 5, multiply each digit by 2.
0
5, 10, 2, 0, 4, 0, 8, 0, 16, 0, 2, 12, 0, 4, 2, 4, 0, 8, 4, 8, 0, 16, 8, 16, 0, 2, 12, 16, 2, 12, 0, 4, 2, 4, 2, 12, 4, 2, 4, 0, 8, 4, 8, 4, 2, 4, 8, 4, 8, 0, 16, 8, 16, 8, 4, 8, 16, 8, 16, 0, 2, 12, 16, 2, 12, 16, 8, 16, 2, 12, 16, 2, 12, 0, 4, 2, 4, 2, 12, 4, 2, 4, 2, 12, 16, 2, 12, 4, 2, 4, 2, 12, 4
OFFSET
1,1
FORMULA
d*2, beginning with 5
EXAMPLE
Read a(2)=10 which produces a(3)=2 & a(4)=0 because 1*2=2 and 0*2=0
Now read a(3)=2 which produces [a(4) is already written] a(5)=4 because 2*2=4.
MATHEMATICA
Flatten[ NestList[ Function[x, Flatten[FromDigits /@ 2IntegerDigits[x]]], 5, 15]] (* Robert G. Wilson v, Feb 21 2005 *)
CROSSREFS
Sequence in context: A091306 A374538 A073048 * A361672 A169841 A084341
KEYWORD
base,easy,nonn
AUTHOR
EXTENSIONS
More terms from Robert G. Wilson v, Feb 21 2005
STATUS
approved