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A245878 Primes p such that p - d and p + d are also primes, where d is the smallest nonzero digit of p. 1
67, 607, 6977, 68897, 69067, 69997, 79867, 80677, 88867, 97967, 609607, 660067, 669667, 676987, 678767, 697687, 707677, 766867, 777677, 786697, 866087, 879667, 880667, 886987, 899687, 906707, 909767, 966997, 990967, 6069977, 6096907, 6097997, 6678877 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Intersection of A245744 and A245745.

The smallest nonzero digit of a(n) is 6, and the least significant digit of a(n) is 7.

LINKS

Table of n, a(n) for n=1..33.

EXAMPLE

The prime 607 is in the sequence because 607 - 6 = 601 and 607 + 6 = 613 are both primes.

PROG

(PARI) s=[]; forprime(p=2, 7000000, v=vecsort(digits(p), , 8); d=v[1+!v[1]]; if(isprime(p-d) && isprime(p+d), s=concat(s, p))); s

(Python)

import sympy

from sympy import isprime

from sympy import prime

for n in range(1, 10**6):

..s=prime(n)

..lst = []

..for i in str(s):

....if i != '0':

......lst.append(int(i))

..if isprime(s+min(lst)) and isprime(s-min(lst)):

....print(s, end=', ')

# Derek Orr, Aug 13 2014

CROSSREFS

Cf. A245742, A245743, A245744, A245745, A245877.

Sequence in context: A163150 A120717 A200963 * A289867 A142139 A178004

Adjacent sequences:  A245875 A245876 A245877 * A245879 A245880 A245881

KEYWORD

nonn,base

AUTHOR

Colin Barker, Aug 05 2014

STATUS

approved

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Last modified September 19 11:33 EDT 2021. Contains 347556 sequences. (Running on oeis4.)