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Numbers k such that the digits of prime(k) end in k.
5

%I #24 Apr 07 2021 20:37:51

%S 7,9551,303027,440999,968819,5517973,27737957,93230839,46492090901,

%T 426836115943,732382677641,4895576080181,77628540590583,

%U 3475456543097857,20396537622790811

%N Numbers k such that the digits of prime(k) end in k.

%C There is no further term up to 115000000. - _Farideh Firoozbakht_, Jan 01 2007

%C a(13) > pi(10^15). - _Donovan Johnson_, May 08 2010

%e Prime(968819) = 14968819 which ends in 968819, so 968819 is a term of the sequence.

%t (* returns true if a ends with b, false otherwise *) f[a_, b_] := Module[{c, d, e, g, h, i, r}, r = False; c = ToString[a]; d = ToString[b]; e = StringLength[c]; g = StringPosition[c, d]; h = Length[g]; If[h > 0, i = g[[h]]; If[i[[2]] == e, r = True]]; r]; Do[If[f[Prime[n], n], Print[n]], {n, 1, 10^6}]

%Y Corresponding primes are in A046883.

%Y Cf. A046883, A068575, A075902.

%K base,nonn

%O 1,1

%A _Joseph L. Pe_, Feb 20 2002

%E a(6) from _Zak Seidov_, Sep 27 2002

%E a(7)-a(8) from _Farideh Firoozbakht_, Jan 01 2007

%E a(9)-a(12) from _Donovan Johnson_, May 08 2010

%E a(13)-a(14) from _Chai Wah Wu_, Apr 05 2021

%E a(15) from _Chai Wah Wu_, Apr 07 2021