|
| |
|
|
A248745
|
|
Primes becoming a composite number if any digit is deleted (zeros allowed).
|
|
1
|
|
|
|
89, 227, 251, 257, 277, 281, 349, 409, 449, 499, 521, 557, 577, 587, 727, 757, 787, 821, 827, 857, 877, 881, 887, 991, 1117, 1129, 1171, 1187, 1259, 1289, 1423, 1447, 1453, 1471, 1483, 1543, 1553, 1559, 1583, 1621, 1669, 1721, 1741, 1747, 1777, 1847, 1889
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
1,1
|
|
|
COMMENTS
|
Since J. Gutierrez called terms of A051362 "super-prime numbers", then it is natural to call the terms of this sequence "weakest primes".
|
|
|
LINKS
|
Peter J. C. Moses, Table of n, a(n) for n = 1..1000
|
|
|
MATHEMATICA
|
compositeQ[n_]:=!(Abs[n]==1||PrimeQ[n]);
Select[Prime[Range[5, 500]], Apply[And, Map[compositeQ[FromDigits[#]]&, Subsets[#, {Length[#]-1}]&[IntegerDigits[#]]]]&] (* Peter J. C. Moses, Oct 13 2014 *)
Select[Prime[Range[300]], AllTrue[FromDigits/@Table[Drop[IntegerDigits[#], {k}], {k, IntegerLength[#]}], CompositeQ]&] (* Harvey P. Dale, Oct 30 2021 *)
|
|
|
CROSSREFS
|
Cf. A051362, A000040.
Sequence in context: A217577 A142826 A251079 * A033257 A145821 A354284
Adjacent sequences: A248742 A248743 A248744 * A248746 A248747 A248748
|
|
|
KEYWORD
|
nonn,base
|
|
|
AUTHOR
|
Vladimir Shevelev, Oct 13 2014
|
|
|
EXTENSIONS
|
More terms from Peter J. C. Moses, Oct 13 2014
|
|
|
STATUS
|
approved
|
| |
|
|
