OFFSET
1,1
COMMENTS
A272701(3) = 27445392 is the least number with the property that sequence focuses on.
If n = a^3 + b^3 = c^3 + d^3 = x^2 + y^4 = z^2 + t^4, then n*k^12 = (a*k^4)^3 + (b*k^4)^3 = (c*k^4)^3 + (d*k^4)^3 = (x*k^6)^2 + (y*k^3)^4 = (z*k^6)^2 + (t*k^3)^4. So if n is this sequence, then n*k^12 is also in this sequence for all k > 1.
EXAMPLE
27445392 is a term because 27445392 = 141^3 + 291^3 = 198^3 + 270^3 = 756^2 + 72^4 = 5076^2 + 36^4.
112416325632 is a term because 112416325632 = 27445392*2^12.
CROSSREFS
KEYWORD
nonn
AUTHOR
Altug Alkan, Jun 19 2016
EXTENSIONS
a(2)-a(18) from Giovanni Resta, Jun 19 2016
STATUS
approved