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%I #11 Nov 14 2022 16:57:23
%S 7,6455,6456,6457,6459,6460,6466,9551,303027,440999,968819,5517973,
%T 27737957,93230839,96664044,46492090901
%N Numbers n such that, as strings, n is a substring of prime(n).
%C pi(2*10^12) < a(17) <= 426836115943. a(18) <= 732382677641. a(19) <= 4895576080181. [From _Donovan Johnson_, May 08 2010]
%e Treated as strings, 6455 is a substring of 64553 = Prime(6455), so 6455 belongs to the sequence.
%e Pairs {n, prime(n)}: {7, 17}, {6455, 64553}, {6456, 64567}, {6457, 64577}, {6459, 64591}, {6460, 64601}, {6466, 64661}, {9551, 99551}, {303027, 4303027}, {440999, 6440999}, {968819, 14968819}, {5517973, 95517973}.
%t Select[Range[10^6], StringPosition[ToString[Prime[ # ]], ToString[ # ]] != {} &]
%t Select[Range[97*10^4],SequenceCount[IntegerDigits[Prime[#]],IntegerDigits[#]]>0&] (* The program generates the first 11 terms of the sequence. *) (* _Harvey P. Dale_, Nov 14 2022 *)
%Y Cf. A067248, A046883, A075902.
%K base,nonn
%O 1,1
%A _Joseph L. Pe_, Mar 26 2002
%E More terms from _Zak Seidov_, Sep 27 2002
%E Three more terms from _Farideh Firoozbakht_, Jan 06 2007
%E a(16) from _Donovan Johnson_, May 08 2010
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