A082622
a(1) = 3, a(n) = smallest palindromic prime obtained by inserting two paired digits anywhere in a(n-1).
Original entry on oeis.org
3, 131, 10301, 1003001, 100030001, 10070307001, 1000703070001, 100075030570001, 10006750305760001, 1000167503057610001, 100015675030576510001, 10001056750305765010001, 1000105367503057635010001, 100001053675030576350100001, 10000105360750305706350100001
Offset: 1
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
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
-
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
A082624
a(1) = 7, a(n) = smallest palindromic prime obtained by inserting digit anywhere in a(n-1).
Original entry on oeis.org
7, 373, 30703, 3007003, 302070203, 30207570203, 3062075702603, 306020757020603, 30602075057020603, 3060320750570230603, 300603207505702306003, 30060320275057202306003, 3006032021750571202306003, 300603202127505721202306003, 30046032021275057212023064003
Offset: 1
Amarnath Murthy and Meenakshi Srikanth (menakan_s(AT)yahoo.com), Apr 29 2003
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