A342832 Sums of two distinct odd fourth powers.

82, 626, 706, 2402, 2482, 3026, 6562, 6642, 7186, 8962, 14642, 14722, 15266, 17042, 21202, 28562, 28642, 29186, 30962, 35122, 43202, 50626, 50706, 51250, 53026, 57186, 65266, 79186, 83522, 83602, 84146, 85922, 90082, 98162, 112082, 130322, 130402, 130946, 132722

Offset

1,1

Links

Table of n, a(n) for n=1..39.

Example

82 is in the sequence since 82 = 1^4 + 3^4.
626 is in the sequence since 626 = 1^4 + 5^4.

Mathematica

Quiet@Select[Range@60000, !Equal@@(a=First@PowersRepresentations[#, 2, 4])&&And@@OddQ@a&] (* Giorgos Kalogeropoulos, Apr 24 2021 *)
Union[Total/@Subsets[Range[1, 19, 2]^4, {2}]] (* Harvey P. Dale, Jan 24 2022 *)

Prog

(Python)
def aupto(limit):
  ofps = [i**4 for i in range(1, int(limit**.25)+2, 2) if i**4 < limit]
  ss = set(f+g for i, f in enumerate(ofps) for g in ofps[i+1:])
  return sorted(s for s in ss if s <= limit)
print(aupto(132722)) # Michael S. Branicky, Apr 24 2021

Crossrefs

Cf. A339992 (sums of two distinct odd cubes), A343588.

Sequence in context: A317212 A282773 A182277 * A186688 A002309 A128959

Adjacent sequences: A342829 A342830 A342831 * A342833 A342834 A342835

Keyword

nonn

Author

Wesley Ivan Hurt, Apr 20 2021

Extensions

More terms from Jon E. Schoenfield, Apr 20 2021

Status

approved