A038474 Sums of two distinct powers of 5.

6, 26, 30, 126, 130, 150, 626, 630, 650, 750, 3126, 3130, 3150, 3250, 3750, 15626, 15630, 15650, 15750, 16250, 18750, 78126, 78130, 78150, 78250, 78750, 81250, 93750, 390626, 390630, 390650, 390750, 391250, 393750, 406250, 468750, 1953126, 1953130, 1953150

Offset

1,1

Links

Amiram Eldar, Table of n, a(n) for n = 1..10000

Mathematica

Union[Total/@Subsets[5^Range[0, 15], {2}]] (* Harvey P. Dale, Jan 06 2011 *)

Prog

(Python)
from itertools import combinations, count, takewhile
def aupto(lim):
  p = takewhile(lambda x: x<= lim, (5**i for i in count(0)))
  t = (sum(c) for c in combinations(p, 2))
  return sorted(filter(lambda x: x <= lim, t))
print(aupto(10**6)) # Michael S. Branicky, Jun 26 2021

Crossrefs

Base 5 interpretation of A038444.

Cf. A000351, A038475, A038476, A038477.

Sequence in context: A045255 A045240 A045225 * A043006 A076284 A177220

Adjacent sequences: A038471 A038472 A038473 * A038475 A038476 A038477

Keyword

nonn,easy

Author

Olivier Gérard

Extensions

Offset changed to 1 and a(37) and beyond from Michael S. Branicky, Jun 26 2021

Status

approved