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A339542
Primes p such that A339541(p) is prime.
2
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
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
KEYWORD
nonn,base
AUTHOR
J. M. Bergot and Robert Israel, Dec 08 2020
STATUS
approved