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A322444 Primes that are not base-8 deletable primes (written in base 10). 1
71, 73, 79, 97, 103, 113, 127, 149, 173, 193, 227, 241, 257, 263, 271, 281, 283, 307, 311, 313, 409, 419, 433, 439, 449, 457, 463, 487, 503, 521, 569, 577, 587, 593, 599, 607, 617, 631, 641, 647, 653, 661, 673, 701, 727, 733, 739, 743, 757, 769, 823, 827, 839, 881, 887, 907, 911, 919, 929 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A prime p is a base-b deletable prime if when written in base b it has the property that removing some digit leaves either the empty string or another deletable prime.

Deleting a digit cannot leave any leading zeros in the new string. For example, deleting the 2 in 2003 to obtain 003 is not allowed.

Complement of all primes and A322443 .

LINKS

Robert Price, Table of n, a(n) for n = 1..660

MATHEMATICA

b = 8; d = {};

p = Select[Range[2, 10000], PrimeQ[#] &];

For[i = 1, i <= Length[p], i++,

c = IntegerDigits[p[[i]], b];

If[Length[c] == 1, AppendTo[d, p[[i]]]; Continue[]];

For[j = 1, j <= Length[c], j++,

t = Delete[c, j];

If[t[[1]] == 0, Continue[]];

If[MemberQ[d, FromDigits[t, b]], AppendTo[d, p[[i]]]; Break[]]]]; Complement[Table[Prime[n], {n, PrimePi[Last[d]]}], d] (* Robert Price, Dec 08 2018 *)

CROSSREFS

Cf. A080608, A080603, A096235-A096246, A321657.

Sequence in context: A104843 A322831 A127316 * A339700 A217414 A159025

Adjacent sequences:  A322441 A322442 A322443 * A322445 A322446 A322447

KEYWORD

nonn,base,easy

AUTHOR

Robert Price, Dec 08 2018

STATUS

approved

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Last modified April 16 12:25 EDT 2021. Contains 343037 sequences. (Running on oeis4.)