A339542 Primes p such that A339541(p) is prime.

2, 13, 19, 37, 71, 73, 127, 163, 167, 181, 271, 293, 307, 367, 431, 433, 457, 503, 569, 631, 659, 811, 907, 983, 1009, 1087, 1153, 1171, 1229, 1373, 1399, 1409, 1423, 1483, 1487, 1511, 1597, 1777, 1801, 1861, 1867, 1999, 2017, 2039, 2053, 2143, 2239, 2273, 2297, 2341, 2383, 2437, 2477, 2521, 2659

Offset

1,1

Comments

Primes p such that p + A138530(p, A007953(p)) is prime.

Links

Robert Israel, Table of n, a(n) for n = 1..10000

Example

a(5) = 71 is in the sequence because sod(71,10) = 8, sod(71,8) = 8 (since 71 = 107_8), and 71+8=79 is prime.

Maple

sod:= proc(x, b) if b=1 then x else convert(convert(x, base, b), `+`) fi end proc:
select(p -> isprime(p+sod(p, sod(p, 10))), [seq(ithprime(i), i=1..1000)]);

Crossrefs

Cf. A007953, A138530, A339541.

Sequence in context: A347259 A181686 A206462 * A020601 A298051 A298656

Adjacent sequences: A339539 A339540 A339541 * A339543 A339544 A339545

Keyword

nonn,base

Author

J. M. Bergot and Robert Israel, Dec 08 2020

Status

approved