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A177511 A053735-perfect numbers. 2
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 (list; graph; refs; listen; history; text; internal format)
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: A058993 A083109 A191590 * 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

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Last modified February 26 09:37 EST 2020. Contains 332277 sequences. (Running on oeis4.)