A082620
a(1) = 1, then the smallest palindromic prime obtained by inserting digits anywhere in a(n-1).
Original entry on oeis.org
1, 11, 101, 10301, 1003001, 100030001, 10003630001, 1000136310001, 100010363010001, 10001036363010001, 1000103639363010001, 100010356393653010001, 10001033563936533010001, 1000103305639365033010001, 100010313056393650313010001, 10001031305636963650313010001
Offset: 1
Amarnath Murthy and Meenakshi Srikanth (menakan_s(AT)yahoo.com), Apr 29 2003
A082621
a(1) = 2, then the smallest palindromic prime obtained by inserting digits anywhere in a(n-1) (including at the ends).
Original entry on oeis.org
2, 727, 37273, 3072703, 307323703, 30073237003, 3006732376003, 300067323760003, 30000673237600003, 3000067382837600003, 300006738242837600003, 30000673820402837600003, 3000063738204028373600003, 300006373821040128373600003, 30000635738210401283753600003
Offset: 1
Amarnath Murthy and Meenakshi Srikanth (menakan_s(AT)yahoo.com), Apr 29 2003
A082623
a(1) = 5, a(n) = smallest palindromic prime obtained by inserting two digits anywhere in a(n-1).
Original entry on oeis.org
5, 151, 10501, 1035301, 103515301, 10325152301, 1013251523101, 101325181523101, 10132512821523101, 1013251428241523101, 101322514282415223101, 10132245142824154223101, 1013224514281824154223101, 101322451402818204154223101, 10132245014028182041054223101
Offset: 1
Amarnath Murthy and Meenakshi Srikanth (menakan_s(AT)yahoo.com), Apr 29 2003
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cp:= proc(x,y) if x[1] < y[1] then true
elif x[1] > y[1] then false
elif nops(x)=1 then true
else procname(x[2..-1],y[2..-1])
fi
end proc: A[1]:= 5: L:= [5]:
for n from 2 to 15 do
nL:= nops(L);
Lp:= sort([seq(seq([op(L[1..i]), x, op(L[i+1..-1])], x=`if`(i=0, 1..9, 0..9)), i=0..nL)], cp);
cands:= map(t -> add(t[i]*(10^(i-1)+10^(2*nL+1-i)), i=1..nL)+t[nL+1]*10^(nL), Lp);
found:= false;
for i from 1 to nops(cands) do
if isprime(cands[i]) then
A[n]:= cands[i];
L:= Lp[i];
found:= true;
break
fi
od;
if not found then break fi
od:
seq(A[i],i=1..15); # Robert Israel, Jan 03 2017, corrected Sep 20 2019
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