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A078832
Smallest prime contained as binary substring in binary representation of n>1, a(1)=1.
3
1, 2, 3, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2
OFFSET
1,2
COMMENTS
a(n)<=3 and for n>1: a(n)>=2 and a(n)=3 iff n=2^k-1, k>1.
a(n) = A225243(n,1). - Reinhard Zumkeller, Aug 14 2013
LINKS
FORMULA
For n > 1: a(n) = A036987(n) + 2. Reinhard Zumkeller, Aug 14 2013
PROG
(Haskell)
a078832 = head . a225243_row -- Reinhard Zumkeller, Aug 14 2013
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Dec 08 2002
STATUS
approved