DIOPHANTINE EQUATIONS DUE TO SMARANDACHE

1) Conjecture:
Let k > 0 be an integer. There is only a finite number of solutions in
integers p, q, x, y, each greater than 1, to the equation
xp - yq = k.
For k = 1 this was conjectured by Cassels (1953) and proved by Tijdeman
(1976).
References:
[1] Ibstedt, H., Surphing on the Ocean of Numbers - A Few Smarandache
Notions and Similar Topics, Erhus University Press, Vail, 1997,
pp. 59-69.
[2] Smarandache, F., Only Problems, not Solutions!, Xiquan Publ. Hse.,
Phoenix, 1994, unsolved problem #20.
2) Conjecture:
Let k >= 2 be a positive integer. The diophantine equation
y = 2x1 x2 ... xk +1
has infinitely many solutions in distinct primes y, x1 , x2 , ..., xk.
References:
[1] Ibstedt, H., Surphing on the Ocean of Numbers - A Few Smarandache
Notions and Similar Topics, Erhus University Press, Vail, 1997,
pp. 59-69.
[2] Smarandache, F., Only Problems, not Solutions!, Xiquan Publ. Hse.,
Phoenix, fourth edition, 1994, unsolved problem #11.