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A345472 Emirps p such that both p and its reversal are sums of three consecutive primes. 1
1151, 1249, 1511, 3467, 3697, 7643, 7963, 9421, 11593, 32749, 36467, 39511, 71329, 76463, 92317, 94723, 110119, 111109, 123707, 124309, 124823, 128377, 141371, 146953, 150383, 155153, 160159, 164291, 167779, 173141, 178223, 184609, 190807, 192383, 192461, 199247, 304193, 304879, 306133, 322871 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Numbers p such that p and its digit reversal are distinct members of A034962.

LINKS

Robert Israel, Table of n, a(n) for n = 1..1792

EXAMPLE

a(4) = 1511 because 1511 and its reversal 1151 are distinct primes, and 1511 = 499+503+509 and 1151 = 379+383+389 are sums of three consecutive primes.

MAPLE

digrev:= proc(n) local L, i;

  L:= convert(n, base, 10);

  add(L[-i]*10^(i-1), i=1..nops(L))

end proc:P:= select(isprime, [2, seq(i, i=3..nextprime(nextprime(333333)), 2)]):

P3:= convert(select(isprime, P[1..-3]+P[2..-2]+P[3..-1]), set):

B:= P3 intersect map(digrev, P3):

sort(convert(remove(t -> digrev(t)=t, B), list);

CROSSREFS

Cf. A006567, A034962.

Sequence in context: A329520 A054999 A086259 * A175606 A179036 A179037

Adjacent sequences:  A345469 A345470 A345471 * A345473 A345474 A345475

KEYWORD

nonn,base

AUTHOR

J. M. Bergot and Robert Israel, Jun 20 2021

STATUS

approved

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Last modified August 10 06:08 EDT 2022. Contains 356029 sequences. (Running on oeis4.)