Problems & Puzzles: Puzzles

Problem 80.  Twin primes generating consecutive...

G. L. Honaker, Jr. sent the following curio and nice puzzle:

5 is the smaller in a set of twin primes whose product is the concatenation of two consecutive primes, (not necessarily twins) i.e., 5*7 = 3.5 (dot is for concatenation.

Q1. Is there one more solution?

There is another curio and puzzle related to the above one:

891077215721081784886888257701070827 is the smaller in a set of twin primes whose product is the concatenation of two consecutive integers, i.e., 891077215721081784886888257701070827*891077215721081784886888257701070829 = 794018604377235322848433897872605582.794018604377235322848433897872605583 (dot is for concatenation).

Q2. Are there more solutions?

note: for both questions the consecutive numbers, in the concatenation, might appear in any of the two orders.


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