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%I #29 Jan 15 2021 01:57:35
%S 2,23,223,373,2237,2337,19373,22337,22373,23773,31373,23373,37337,
%T 223737,223773,223373,233137,233373,237337,1137337,1937337,1373373,
%U 2233733,2233137,373373,2233373,2337313,2237337,2237373,2337353,3733313,2331373,3137337,3137373,3373373,2337373,2337337,2373373
%N a(n) is the first number whose digit sequence can be partitioned into primes in exactly n ways.
%H Robert Israel, <a href="/A340296/b340296.txt">Table of n, a(n) for n = 1..93</a>
%e For n=4, a(4) = 373 can be partitioned into primes in four ways: 3|7|3, 3|73, 37|3 and 373.
%p f:= proc(n) option remember; local i,t;
%p if isprime(n) then t:= 1 else t:= 0 fi;
%p for i from 1 to ilog10(n) do
%p if isprime(n mod 10^i) then t:= t + procname(floor(n/10^i)) fi
%p od;
%p t
%p end proc:
%p f(0):= 0:
%p V:= Vector(38):
%p for n from 2 to 10^7 do
%p v:= f(n);
%p if v > 0 and v <= 38 and V[v] = 0 then V[v]:= n fi
%p od:
%p convert(V,list);
%K nonn,base
%O 1,1
%A _J. M. Bergot_ and _Robert Israel_, Jan 14 2021
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