A261511 Twin primes with both terms having distinct digits in descending order.

3, 5, 7, 41, 43, 71, 73, 641, 643, 76541, 76543, 87641, 87643

Offset

1,1

Comments

Numbers in this list are the pairs of twin primes listed in A052014 with both terms having distinct digits in descending order

Links

Table of n, a(n) for n=1..13.

Mathematica

dsc[n_] := 0 > Max@ Differences@ IntegerDigits@n; Union@ Flatten@ Select[ Partition[ Prime@ Range@ 9000, 2, 1], #[[2]] - #[[1]] == 2 && And @@ dsc /@ # &] (* Giovanni Resta, Aug 26 2015 *)

Prog

(PARI) lista(nn=100000) = {v = []; forprime(p=2, nn, if (isprime(p+2) && (d=digits(p)) && (vecsort(d, , 12)==d) && (dd=digits(p+2)) && (vecsort(dd, , 12)==dd), v = concat(v, p); v = concat(v, p+2)); ); vecsort(v, , 8); } \\ Michel Marcus, Aug 23 2015

Crossrefs

Cf. A001097, A052014.

Sequence in context: A163797 A339900 A130536 * A146972 A102742 A363965

Adjacent sequences: A261508 A261509 A261510 * A261512 A261513 A261514

Keyword

nonn,easy,fini,full,base

Author

Paolo Omodei-Zorini, Aug 22 2015

Status

approved