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A253775 Numbers representable as x^y + x + y, where x>1, y>1 are integers (without multiplicity). 8
8, 13, 14, 22, 32, 33, 39, 44, 58, 71, 72, 74, 88, 92, 112, 133, 134, 137, 158, 184, 212, 225, 242, 251, 264, 266, 274, 308, 344, 353, 382, 422, 464, 508, 523, 554, 602, 634, 652, 704, 738, 741, 758, 814, 872, 932, 994, 1013, 1033, 1036, 1058, 1124, 1192, 1262, 1306 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Jean-François Alcover, Table of n, a(n) for n = 1..1000

EXAMPLE

a(1) = 8 = 2^2 + 2 + 2.

a(2) = 13 = 2^3 + 2 + 3.

a(3) = 14 = 3^2 + 3 + 2.

a(4) = 22 = 2^4 + 2 + 4 = 4^2 + 4 + 2. - Wolfdieter Lang, Feb 03 2015

MAPLE

N:= 10000; # to get all terms <= N

select(`<=`, {seq(seq(x^y+x+y, y = 2..floor(log[x](N-x))),

      x=2..floor(sqrt(N)))}, N);

# if using Maple 11 or earlier, uncomment the next line

# sort(convert(%, list)); # Robert Israel, Jan 14 2015

MATHEMATICA

M = 2000;

Select[Table[x^y + x + y, {x, 2, Floor[Sqrt[M]]}, {y, 2, Floor[Log[x, M-x]] }] // Flatten, # <= M&] // Union (* Jean-François Alcover, Feb 27 2019, after Robert Israel *)

CROSSREFS

Cf. A253776, A253777.

Sequence in context: A133192 A063684 A059194 * A168137 A252458 A271720

Adjacent sequences:  A253772 A253773 A253774 * A253776 A253777 A253778

KEYWORD

nonn

AUTHOR

Alex Ratushnyak, Jan 12 2015

STATUS

approved

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Last modified June 16 04:54 EDT 2019. Contains 324145 sequences. (Running on oeis4.)