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A027564 Numbers not of form abcd + abce + abde + acde + bcde for 1 <= a <= b <= c <= d <= e. 4
1, 2, 3, 4, 6, 7, 8, 10, 11, 12, 14, 15, 18, 19, 20, 22, 24, 26, 27, 31, 32, 34, 35, 36, 38, 39, 42, 46, 47, 50, 54, 55, 59, 60, 62, 66, 67, 70, 71, 75, 78, 84, 87, 90, 92, 94, 98, 99, 102, 104, 106, 110, 111, 115, 116, 119, 122, 126, 127, 130, 131, 132, 138 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Robert Israel, Table of n, a(n) for n = 1..1578

MAPLE

N := 1000: # for all terms <= N

V:= Vector(N):

for a from 1 to floor((N/5)^(1/4)) do

  for b from a while 4*a*b^3+b^4<= N do

    for c from b while 3*a*b*c^2 + (a+b)*c^3 <= N do

      for d from c while 2*a*b*c*d + (b*c+a*c+a*b)*d^2 <= N do

        for e from d do

          r:= a*b*c*d+a*b*c*e+a*b*d*e+a*c*d*e+b*c*d*e;

          if r > N then break fi;

          V[r]:= 1;

od od od od od:

select(t -> V[t]=0, [$1..N]); # Robert Israel, Nov 04 2018

CROSSREFS

Cf. A025052, A027563, A027565, A027566.

Sequence in context: A029597 A188262 A099619 * A284941 A248559 A186511

Adjacent sequences:  A027561 A027562 A027563 * A027565 A027566 A027567

KEYWORD

nonn,fini

AUTHOR

R. H. Hardin

STATUS

approved

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Last modified April 12 12:39 EDT 2021. Contains 342920 sequences. (Running on oeis4.)