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Smaller of two consecutive prime numbers with the same digital product.
2

%I #8 Dec 03 2023 11:26:51

%S 101,103,107,401,503,601,701,1009,1013,1019,1021,1031,1033,1039,1049,

%T 1051,1061,1063,1069,1087,1091,1093,1097,1103,1301,1303,1601,1607,

%U 1901,1913,2003,2011,2017,2027,2029,2039,2053,2063,2069,2081,2083,2087,2089

%N Smaller of two consecutive prime numbers with the same digital product.

%H Harvey P. Dale, <a href="/A117837/b117837.txt">Table of n, a(n) for n = 1..1000</a>

%e 1913 and 1931 are two consecutive primes and have te same digital product.

%t sdpQ[{a_,b_}]:=Times@@IntegerDigits[a]==Times@@IntegerDigits[b]; Select[ Partition[Prime[Range[400]],2,1],sdpQ][[All,1]] (* _Harvey P. Dale_, Jul 27 2020 *)

%t Prime[#]&/@SequencePosition[Table[Times@@IntegerDigits[p],{p,Prime[Range[ 400]]}],{x_,x_}][[;;,1]] (* _Harvey P. Dale_, Dec 03 2023 *)

%K base,nonn

%O 1,1

%A Luc Stevens (lms022(AT)yahoo.com), Apr 30 2006