%I A110194
%S A110194 1,8,1,4,1,1,4,1,1,4,1,1,4,1,1,1,1,4,4,1,1,4,1,1,4,1,1,4,1,1,1,1,4,4,1,
%T A110194 1,1,1,4,4,1,1,4,1,1,1,1,4,4
%N A110194 First differences of A110095 (least nonprime sequence whose first differences
are nonprime).
%C A110194 Conjecture: from a(5) on, are there only substrings <1 1 4> and <1 1
1 1 4 4 >?
%e A110194 Beginning with 1, we have to add 8 in order to get the first nonprime
number (all other numbers <8 are prime or giving a prime). So 1+8=9
for a(2).
%e A110194 Then add 1=10 for a(3).
%e A110194 Then add (not 1 because 11 is prime; nor 2 and 3 because they are prime)
...add 4=14 for a(4), etc.
%Y A110194 Cf. A110095 and twin-primes related sequences.
%Y A110194 Sequence in context: A093602 A011469 A140457 this_sequence A079359 A010156
A154190
%Y A110194 Adjacent sequences: A110191 A110192 A110193 this_sequence A110195 A110196
A110197
%K A110194 easy,nonn
%O A110194 1,2
%A A110194 Alexandre Wajnberg & Eric Angelini (alexandre.wajnberg(AT)ulb.ac.be),
Sep 06 2005
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