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A141757 Even terms in A100933. 3
50, 98, 150, 242, 250, 294, 338, 350, 490, 550, 578, 650, 686, 722, 726, 750, 850, 950, 1014, 1050, 1058, 1078, 1150, 1210, 1274, 1450, 1470, 1550, 1650, 1666, 1682, 1690, 1694, 1734, 1750, 1850, 1862, 1922, 1950, 2050, 2058, 2150, 2166, 2254, 2350, 2366 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..46.

MAPLE

with(numtheory):

# For A100549: if n = prod_p p^e_p, then pp = largest prime <= 1 + max e_p

pp := proc(n) local f, m; option remember;

if (n = 1) then

return 1;

end if;

m := 1:

for f in op(2..-1, ifactors(n)) do

if (f[2] > m) then

m := f[2]:

end if;

end do;

prevprime(m+2);

end proc;

# For A100762: B = prod_{p <= pp(n)} p^e_p

B := proc(n) local v, f, pv; global pp; option remember;

pv := pp(n);

v := 1:

for f in op(2..-1, ifactors(n)) while f[1] <= pv do

v := v * f[1]^f[2];

end do;

return v;

end proc;

# For A100417: Bgood = (is pp(n) = pp(B(n))), that is, is B(n) enough to establish pp(n)?

Bgood := proc(n) global pp;

`if`(pp(B(n))=pp(n), true, false);

end proc;

# For A100933 and A141757:

t0:=select(not Bgood, [$1..3000]);

t1:=[];

for n from 1 to nops(t0) do

if t0[n] mod 2 = 0 then t1:=[op(t1), t0[n]]; fi; od: t1;

CROSSREFS

Sequence in context: A255585 A260901 A090997 * A248023 A044139 A044520

Adjacent sequences:  A141754 A141755 A141756 * A141758 A141759 A141760

KEYWORD

nonn

AUTHOR

David Applegate and N. J. A. Sloane, Sep 15 2008

STATUS

approved

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Last modified February 21 04:18 EST 2019. Contains 320371 sequences. (Running on oeis4.)