Re Primes with initial digits - errors: one seq. left to check
N. J. A. Sloane
njas at research.att.com
Sat Jan 27 15:08:17 CET 2007
Dear seqfan,
I submitted five sequences about the primes of level(1,i), levels(1,12 to 16).
Def : Let p(i) denote the i-th prime. If 2 p(n) - p(n+1) (or p(n) - g(n)) is a
prime, say p(n-i), then we say that p(n) has level(1,i), with g(n) = p(n+1) -
p(n).
p(50000000)= 982451653.
On the first 50 million primes, I found only on level (1,17) :
prime(19517159)=364058659
prime(19517160)-prime(19517159)=prime(19517159)-prime(19517159-17),
prime(19517160)-prime(19517159)=prime(19517159)-prime(19517142),
364058839 - 364058659 = 364058659 - 364058479=180=6*30,
prime(19517159) has a level 1 in A117563,
prime(19517159)= 364058659 has a level(1,17).
More values are welcome.
Best,
Rémi
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