ROSECODE 374
Pandigital never prime
Consider the number 100020
If you change one of its digits, you never get a prime number:
100020=
200020=
300020=
400020=
500020=
600020=
700020=
800020=
900020=
100020=
110020=
120020=
130020=
140020=
150020=
160020=
170020=
180020=
190020=
100020=
101020=
102020=
103020=
104020=
105020=
106020=
107020=
108020=
109020=
100020=
100120=
100220=
100320=
100420=
100520=
100620=
100720=
100820=
100920=
100000=
100010=
100020=
100030=
100040=
100050=
100060=
100070=
100080=
100090=
100020=
100021=
100022=
100023=
100024=
100025=
100026=
100027=
100028=
100029=
What is the smallest pandigital number (in base 10) with that property? (*)
(*) All the numbers you get when changing one digit must be pandigital too.
[My timing: < 1 sec]
If you change one of its digits, you never get a prime number:
100020=
200020=
300020=
400020=
500020=
600020=
700020=
800020=
900020=
100020=
110020=
120020=
130020=
140020=
150020=
160020=
170020=
180020=
190020=
100020=
101020=
102020=
103020=
104020=
105020=
106020=
107020=
108020=
109020=
100020=
100120=
100220=
100320=
100420=
100520=
100620=
100720=
100820=
100920=
100000=
100010=
100020=
100030=
100040=
100050=
100060=
100070=
100080=
100090=
100020=
100021=
100022=
100023=
100024=
100025=
100026=
100027=
100028=
100029=
What is the smallest pandigital number (in base 10) with that property? (*)
(*) All the numbers you get when changing one digit must be pandigital too.
[My timing: < 1 sec]