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Numbers with two or more digits such that every two consecutive digits are a square.
1

%I #24 Aug 23 2017 03:16:52

%S 16,25,36,49,64,81,164,364,649,816,1649,3649,8164,81649

%N Numbers with two or more digits such that every two consecutive digits are a square.

%C The largest number in this sequence (81649) is the only prime in the sequence.

%e 164 is in this sequence because 16 and 64 are both squares.

%o (PARI) is(n)=if(n<16, return(0)); while(n>9, if(!issquare(n%100), return(0)); n\=10); 1 \\ _Charles R Greathouse IV_, Aug 23 2017

%K base,fini,full,nonn,easy

%O 1,1

%A _Bobby Jacobs_, Aug 22 2017