OFFSET
1,1
COMMENTS
All terms with more than a single digit must comprise only the digits 1, 4, and 7, because no number comprising the digits 2, 5, and 8 or the digits 3, 6, and 9 can be prime. - Harvey P. Dale, Mar 01 2023
LINKS
Sean A. Irvine, Table of n, a(n) for n = 1..1000
MATHEMATICA
Join[{2, 3, 5, 7}, Table[Select[FromDigits/@Tuples[{1, 4, 7}, n], PrimeQ[#]&& Union[ Abs[ Differences[ IntegerDigits[ #]]]]=={3}&], {n, 11}]//Flatten] (* Harvey P. Dale, Mar 01 2023 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Patrick De Geest, Apr 15 1999
EXTENSIONS
More terms from Naohiro Nomoto, Jul 28 2001
More terms from Sean A. Irvine, Jun 15 2021
STATUS
approved