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A213175
Primes p such that subtracting two from any single decimal digit of p produces another prime with restriction that first digit may not be changed to a 0 (obviously p cannot contain digits less than 2).
0
5, 7, 43, 73, 463, 859, 883, 3559, 3823, 4273, 77269
OFFSET
1,1
COMMENTS
Starting from composites instead of primes we obtain much larger terms, like 92997492273. - Giovanni Resta, Feb 27 2013
LINKS
G. L. Honaker, Jr. and Chris Caldwell, Prime Curios! 77269
Carlos Rivera, Puzzle 377
EXAMPLE
463 belongs to this sequence because 463, 461, 443 and 263 are all prime.
MATHEMATICA
apQ[p_]:=Module[{id=IntegerDigits[p]}, id[[1]]>2&&Min[id]>1&&AllTrue[Table[p-(2*10^d), {d, 0, IntegerLength[p]-1}], PrimeQ]]; Select[Prime[Range[80000]], apQ] (* Harvey P. Dale, Aug 24 2024 *)
CROSSREFS
Sequence in context: A292010 A064082 A274907 * A265786 A090520 A066219
KEYWORD
nonn,base,fini,full
AUTHOR
STATUS
approved