A038466 Sums of 4 distinct powers of 3.

40, 94, 112, 118, 120, 256, 274, 280, 282, 328, 334, 336, 352, 354, 360, 742, 760, 766, 768, 814, 820, 822, 838, 840, 846, 976, 982, 984, 1000, 1002, 1008, 1054, 1056, 1062, 1080, 2200, 2218, 2224, 2226, 2272, 2278, 2280, 2296, 2298, 2304, 2434, 2440, 2442, 2458

Offset: 1

Author

Olivier Gérard

Keywords

• nonn
• easy

Links

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

Crossrefs

Base 3 interpretation of A038446.

Cf. A000244, A038464, A038465, A038467, A038468, A038469.

Programs

Mathematica

Sort[Plus @@@ Subsets[3^Range[0, 7], {4}]] (* Amiram Eldar, Jul 13 2022 *)

Python

from itertools import islice
def A038466_gen(): # generator of terms
    yield int(bin(n:=15)[2:],3)
    while True: yield int(bin((n:=n^((a:=-n&n+1)|(a>>1)) if n&1 else ((n&~(b:=n+(a:=n&-n)))>>a.bit_length())^b))[2:],3)
A038466_list = list(islice(A038466_gen(),30)) # Chai Wah Wu, Apr 04 2025

Extensions

Offset corrected by Amiram Eldar, Jul 13 2022