A109309 Larger emirps (primes whose digit reversal is a lesser prime).

31, 71, 73, 97, 311, 701, 733, 743, 751, 761, 907, 937, 941, 953, 967, 971, 983, 991, 1201, 1301, 1321, 1511, 1601, 1741, 1811, 1831, 1901, 3011, 3121, 3191, 3203, 3221, 3251, 3271, 3301, 3371, 3391, 3433, 3511, 3541, 3571, 3613, 3643, 3733, 3803, 3821

Offset

1,1

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Mathematica

dr[n_]:=FromDigits[Reverse[IntegerDigits[n]]]; Select[Prime[Range[1000]], PrimeQ[dr[ # ]]&&dr[ # ]<#&]
Select[Prime[Range[600]], PrimeQ[IntegerReverse[#]]&&#>IntegerReverse[#]&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jul 23 2020 *)

Crossrefs

Cf. A006567 Emirps (primes whose digit reversal is a different prime), A109308 Lesser emirps (primes whose digit reversal is a larger prime).

Sequence in context: A193573 A086042 A086051 * A263242 A294625 A304292

Adjacent sequences: A109306 A109307 A109308 * A109310 A109311 A109312

Keyword

base,nonn

Author

Zak Seidov, Jun 25 2005

Status

approved