A277689 Primes that become palindromic primes when the most significant digit is deleted.

13, 17, 23, 37, 43, 47, 53, 67, 73, 83, 97, 103, 107, 211, 307, 311, 503, 607, 811, 907, 911, 1151, 1181, 1373, 1787, 2003, 2011, 2131, 2383, 2797, 3011, 3181, 3191, 3313, 3373, 3727, 3797, 3919, 3929, 4003, 4007, 4373, 4787, 4919, 5003, 5011, 5101, 6007

Offset

1,1

Links

Chai Wah Wu, Table of n, a(n) for n = 1..13189 (a(n) for n = 1..1000 from Colin Barker).

Mathematica

ppQ[n_]:=Module[{c=FromDigits[Rest[IntegerDigits[n]]]}, PrimeQ[c] && PalindromeQ[ c]]; Select[Prime[Range[1000]], ppQ] (* Harvey P. Dale, Aug 04 2018 *)

Prog

(PARI) rotl(a) = my(b, c, d); b=#Str(a); c=floor(a/(10^(b-1))); d=a-c*(10^(b-1)); 10*d+c
revint(n) = m=n%10; n\=10; while(n>0, m=m*10+n%10; n\=10); m
L=List(); forprime(n=2, 100000, r=rotl(n)\10; if(isprime(r) && revint(r)==r, listput(L, n))); Vec(L)

Crossrefs

Cf. A234912, A235000, A277206.

Sequence in context: A038680 A227916 A158072 * A240894 A244078 A126143

Adjacent sequences: A277686 A277687 A277688 * A277690 A277691 A277692

Keyword

nonn,base

Author

Colin Barker, Apr 11 2017

Status

approved