A307474 - OEIS

A307474

SanD-68 primes p: such that p+d is also prime and sum of digits A007953(p(p+d)) = d, with d = 68.

19961, 28211, 43541, 44111, 62861, 66821, 69941, 83621, 86561, 88721, 89261, 92111, 94781, 99191, 120671, 125261, 129461, 129959, 130211, 132173, 132611, 136709, 138071, 141209, 141371, 150959, 153191, 156071, 157211, 158009, 159521, 161459, 163673, 164231, 165161, 165311, 167261, 170111, 171401, 178571

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OFFSET

1,1

COMMENTS

SanD-d primes exist only for d = 14 + 18*k, k = -1/2, 0, 1, 2, 3, ...

This is the sequence for k = 3. See cross-references for other k and related sequences, in particular the main entry A307479 with further references.

LINKS

Table of n, a(n) for n=1..40.

EXAMPLE

a(1) = 19961 = A307479(186) = A307480(3) is the smallest SanD-68 prime: 19961 and 19961 + 68 = 20029 both are prime, and the digit sum A007953(19961*20029) = 3+9+9+7+9+8+8+6+9 = 68.

PROG

(PARI) print_A307474(N=100, d=68)=forprime(p=2, , isprime(p+d)&&sumdigits(p*(p+d))==d&&!print1(p, ", ")&&!N--&&break)

CROSSREFS

Cf. A307471 - A307478 (d = 14+18k, k=0..7), A307479 (any d: main entry), A307480 (smallest prime for given d).

Cf. A000040 (primes), A007953 (sum of digits).

Sequence in context: A175590 A324594 A203045 * A206009 A035926 A090072

Adjacent sequences: A307471 A307472 A307473 * A307475 A307476 A307477

KEYWORD

nonn,base

AUTHOR

M. F. Hasler, Apr 09 2019

EXTENSIONS

Type in a(40) corrected by Seth A. Troisi, May 17 2022

STATUS

approved