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List of k primes ending in k, where k == 1, 3, 7 or 9 (mod 10).
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%I #11 Apr 24 2024 08:20:38

%S 11,3,13,23,7,17,37,47,67,97,107,19,29,59,79,89,109,139,149,179,11,

%T 211,311,811,911,1511,1811,2011,2111,2311,2411,13,113,313,613,1013,

%U 1213,1613,1913,2113,2213,2713,3313,3413,17,317,617,1117,1217,2017,2417,2617

%N List of k primes ending in k, where k == 1, 3, 7 or 9 (mod 10).

%C Lists the 1st entry in A030430, the first 3 entries of A030431, the first 7 entries of A030432, the first 9 entries of A030433, the first 11 entries of A167442 etc.

%e Terms corresponding to 7 are 7, 17, 37, 47, 67, 97, 127. 13 occurs for 3 as well as for 13.

%e 11;

%e 3,13,23;

%e 7,17,37,47,67,97,107;

%e 19,29,59,79,89,109,139,149,179;

%t f[n_] := Take[ Select[p, Mod[ #, 10^Floor[ Log[10, n] + 1]] == n &], n]; p = Prime[ Range[10^5]]; lst = Select[ Range[1, 17, 2], Mod[ #, 10] != 5 &] (* _Robert G. Wilson v_ *)

%Y Cf. A089779, A088262.

%K base,easy,nonn,tabf

%O 1,1

%A _Amarnath Murthy_, Jul 30 2005

%E Corrected and extended by _Robert G. Wilson v_, Jul 30 2005