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 An equation with consecutive primes (Posted on 2006-01-16)
The equation below involves four 5-digits prime numbers:

A + B + C = D

A, B and C are consecutives, B and D are palindromes.

Find A, B, C and D.

 See The Solution Submitted by pcbouhid Rating: 3.0000 (2 votes)

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 computer solution -- spoiler | Comment 1 of 23

The UBASIC program:

`   10   P1=nxtprm(9999)   20   P2=nxtprm(P1)   30   P3=nxtprm(P2)   40   while P3<100000   50     P2t=cutspc(str(P2))   55     Good=1   60     for I=1 to int(len(P2t)/2)   70       if mid(P2t,I,1)<>mid(P2t,len(P2t)-I+1,1) then Good=0   80     next   90     if Good then  100      :P4=P1+P2+P3  110      :if nxtprm(P4-1)=P4 then  120         :P4t=cutspc(str(P4))  130         :for I=1 to int(len(P4t)/2)  140           :if mid(P4t,I,1)<>mid(P4t,len(P4t)-I+1,1) then Good=0:endif  150         :next  160         :if Good then print P1;P2;P3;P4  170     P1=P2:P2=P3:P3=nxtprm(P2)  180   wend`

finds A,B,C and D as:

` 10499  10501  10513  31513`

 Posted by Charlie on 2006-01-16 09:40:56

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