A178093 -id:A178093 - cp's OEIS frontend

A178092 Lesser of emirp pairs whose digital sums are also emirps (A178091).

157, 179, 337, 359, 1097, 1237, 1259, 1381, 1439, 1453, 1471, 1583, 1619, 1723, 3019, 3109, 3163, 3257, 3343, 3347, 3527, 7699, 7879, 9679, 10039, 10079, 10273, 10453, 10457, 10651, 10781, 10853, 11083, 11159, 11353, 11447, 11551, 11717, 11731, 11933, 12073

Offset: 1

Lekraj Beedassy, May 19 2010

Harvey P. Dale, Table of n, a(n) for n = 1..10000

Cf. A109308, A178091, A178093.

emrp[n_]:=Module[{e=FromDigits[Reverse[IntegerDigits[n]]]},If[n!=e&&PrimeQ[ e],{n,e},{}]]; dsemQ[m_]:=Module[ {ds=Total[IntegerDigits[m]],em}, em= FromDigits[ Reverse[IntegerDigits[ ds]]];em!=ds&& And@@PrimeQ[{ds,em}]]; Select[Transpose[Rest[Union[Sort/@(emrp/@Prime[Range[2000]])]]][[1]],dsemQ] (* Harvey P. Dale, Sep 11 2013 *)

Corrected and extended by Harvey P. Dale, Sep 11 2013

A178091 Emirps whose digital sums are also emirps.

Original entry on oeis.org

157, 179, 337, 359, 733, 751, 953, 971, 1097, 1237, 1259, 1381, 1439, 1453, 1471, 1583, 1619, 1723, 1741, 1831, 3019, 3109, 3163, 3257, 3271, 3343, 3347, 3433, 3527, 3541, 3613, 3851, 7253, 7321, 7433, 7523, 7699, 7879, 7901, 9013, 9103, 9161, 9341, 9521, 9679, 9769, 9787, 9967

Offset: 1

Lekraj Beedassy, May 19 2010

Palindromic primes are not allowed, nor are palindromic digital sums of primes. - Harvey P. Dale, Feb 23 2014

Amiram Eldar, Table of n, a(n) for n = 1..10000 (terms 1..1000 from Harvey P. Dale)
Silva, Prime Curios, Entry 157.

Cf. A006567, A178092, A178093.

dseQ[n_]:=Module[{idn=IntegerDigits[n],ds},ds=IntegerDigits[Total[idn]];idn!=Reverse[idn]&&ds!=Reverse[ds] && And@@PrimeQ[{FromDigits[ Reverse[ idn]],FromDigits[ds],FromDigits[Reverse[ds]]}]]; Select[Prime[Range[ 1300]],dseQ] (* Harvey P. Dale, Feb 23 2014 *)

cp's OEIS Frontend

A178092 Lesser of emirp pairs whose digital sums are also emirps (A178091).

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