OFFSET
1,1
COMMENTS
Numbers n such that n and R(n) are both of the form a^3-b^3 with a > b > 0.
EXAMPLE
19 = 3^3 - 2^3 and 91 = 6^3 - 5^3.
MATHEMATICA
t1 = Select[ Union[ Flatten[ Table[n^3 - m^3, {n, 185}, {m, 0, n - 1}]]], # < 10^5 && Mod[ #, 10] != 0 &]; t2 = FromDigits /@ Reverse /@ IntegerDigits /@ t1; Take[ Intersection[t1, t2], 40] (* Robert G. Wilson v, Jul 14 2005 *)
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Jul 10 2005
EXTENSIONS
Edited and extended by Robert G. Wilson v, Jul 14 2005
STATUS
approved