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A330160 Positions of 2 in A309059. 0
3, 7, 10, 15, 22, 45, 227, 700, 5170, 11147, 11869 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
FORMULA
A309059(a(n))=2.
EXAMPLE
a(3)=10 is in the sequence because A309059(10)=2.
MAPLE
x:= 1: Res:= NULL:
for i from 2 to 10000 do
if isprime(x) then Res:= Res, i; x:= 10*x+2;
else x:= 10*x+1
fi
od:
Res;
CROSSREFS
Cf. A309059.
Sequence in context: A353654 A143101 A307612 * A281642 A353427 A121016
KEYWORD
nonn,more
AUTHOR
Robert Israel, Dec 03 2019
EXTENSIONS
a(10) and a(11) from Robert Israel, Dec 17 2019
STATUS
approved

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Last modified March 29 00:26 EDT 2024. Contains 371264 sequences. (Running on oeis4.)