A177511 A053735-perfect numbers.

3, 26, 62, 74, 77, 133, 134, 143, 155, 161, 185, 203, 206, 209, 215, 218, 319, 323, 341, 386, 398, 458, 473, 542, 545, 551, 554, 562, 565, 581, 589, 611, 614, 629, 635, 662, 671, 695, 698, 703, 706, 707, 713, 718, 721, 889, 899, 913, 959, 965, 998

Offset

1,1

Comments

For definition, see A175522.

Links

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

Formula

{n : sum_{d|n, d<n} A053735(d) = A053735(n)}.

Maple

A053735 := proc(n) add(d, d=convert(n, base, 3)) ; end proc:
isA177511 := proc(n) local a, d ; a := 0 ; for d in numtheory[divisors](n) minus {n} do a := a+A053735(d) ; end do: a = A053735(n) ; end proc:
for n from 1 to 1000 do if isA177511(n) then printf("%d, ", n) ; end if; end do: # R. J. Mathar

Prog

(Sage) A053735 = lambda n: sum(n.digits(base=3))
is_A177511 = lambda n: sum(A053735(d) for d in divisors(n)) == 2*A053735(n)
# D. S. McNeil, Dec 11 2010
(PARI) isok(n) = sumdiv(n, d, (d<n)* vecsum(digits(d, 3))) == vecsum(digits(n, 3)); \\ Michel Marcus, Feb 06 2016

Crossrefs

Cf. A175522, A000396, A175807, A175853, A176234, A177084, A177050.

Sequence in context: A083109 A191590 A354050 * A294494 A048372 A269342

Adjacent sequences: A177508 A177509 A177510 * A177512 A177513 A177514

Keyword

nonn,base

Author

Vladimir Shevelev, Dec 11 2010

Extensions

Extended by D. S. McNeil, Dec 11 2010

Status

approved