OFFSET
1,1
COMMENTS
n, 10*n, 10*n+4, 10*n+6 and 10*n+8 are all in the sequence if any one of them is. - Robert Israel, Mar 21 2019
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
EXAMPLE
a(1) = 113 because "3" and "11" and "13" and "113" are prime substrings of "113".
MAPLE
filter:= proc(n) local L, m, SS, S, count, i, j;
L:= convert(n, base, 10);
m:= nops(L);
SS:= remove(t -> t[-1]=0, {seq(seq(L[i..j], j=i..m), i=1..m)});
nops(select(isprime, map(S -> add(S[i]*10^(i-1), i=1..nops(S)), SS))) = 4
end proc:
select(filter, [$100..1000]); # Robert Israel, Mar 21 2019
CROSSREFS
KEYWORD
base,easy,nonn
AUTHOR
Gil Broussard, Aug 03 2009
STATUS
approved