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Irregular triangle, read by rows, of primes with suffix n and digits "1" prepended , otherwise 0.
2

%I #5 Mar 30 2012 18:35:54

%S 11,0,13,113,0,0,0,17,0,19,0,0,0,113,0,0,0,0,0,0,0,0,0,0,0,0,0,127,0,

%T 0,0,131,0,0,0,0,0,137,0,139,0,0,0,0,0,0,0,0,0,149,0,151,1151,0,0,0,0,

%U 0,157,0,0,0,0,0,163,1163,0,0,0,167,0,0,0,0,0,173,0,0,0,0,0,179

%N Irregular triangle, read by rows, of primes with suffix n and digits "1" prepended , otherwise 0.

%C Row n ends when a composite number is found.

%e for k=1..2 , a(3, k) = {13, 113} are in the sequence.

%p with(numtheory): for n from 1 to 100 do:a0:=n:id:=0:c:=0:for k from 1 to 20

%p while (id=0) do:d:=length(a0):a1:=10^d+a0:if type(a1, prime)=true then a0:=a1:printf(`%d,

%p `, a0):c:=c+1:else id:=1:fi:od:if c=0 then printf(`%d, `, 0):else fi:od:

%Y Cf. A186071 A185682, A185684, A185685, A185687.

%K nonn,base,tabf

%O 1,1

%A _Michel Lagneau_, Feb 11 2011