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Beginning with 2, primes of the form: least multiple of the previous term followed by a 7. Beginning with 2, a(n) is the least prime of the form k*a(n-1)*10 +7.
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%I #9 Nov 14 2021 17:35:51

%S 2,47,947,18947,947357,47367857,4263107137,682097141927,

%T 545677713541607,65481325624992847,21608837456247639517,

%U 4105679116687051508237,944306196838021846894517

%N Beginning with 2, primes of the form: least multiple of the previous term followed by a 7. Beginning with 2, a(n) is the least prime of the form k*a(n-1)*10 +7.

%H Michael De Vlieger, <a href="/A112783/b112783.txt">Table of n, a(n) for n = 1..300</a>

%t NestList[Block[{k = 1, m}, While[! PrimeQ[Set[m, 10 k # + 7]], k++]; m] &, 2, 12] (* _Michael De Vlieger_, Nov 14 2021 *)

%Y Cf. A112782, A112784.

%K base,nonn

%O 1,1

%A _Amarnath Murthy_, Jan 02 2006

%E More terms from _Joshua Zucker_, Jan 11 2006