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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

Table of n, a(n) for n=1..11.

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: A320441 A143101 A307612 * A281642 A121016 A246701

Adjacent sequences:  A330157 A330158 A330159 * A330161 A330162 A330163

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 February 26 09:44 EST 2020. Contains 332277 sequences. (Running on oeis4.)