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A174434 Numbers in A093891, but not A005153. 1
10, 70, 350, 490, 572, 770, 836, 910, 1190, 1330, 1430, 1610, 1750, 1870, 2030, 2090, 2170, 2210, 2470, 2530, 2584, 2590, 2750, 2870, 2990, 3010, 3128, 3190, 3230, 3250, 3290, 3410, 3430, 3710, 3850, 3944, 4130, 4216, 4270, 4550, 4690, 5032, 5390, 5576 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A number n is in this sequence if the sums of distinct divisors of n form all the primes up to sigma(n), but do not form all the integers up to sigma(n).

LINKS

Table of n, a(n) for n=1..44.

MATHEMATICA

Test[n_] := Module[{d=Divisors[n], t, lim, x}, t=CoefficientList[Product[1+x^i, {i, d}], x]; lim=PrimePi[Length[t]-1]; Count[t[[1+Prime[Range[lim]]]], _?(#>0&)] == lim && Count[t, 0] > 0]; Select[Range[1000], Test]

CROSSREFS

Sequence in context: A025221 A271040 A005567 * A073391 A002802 A101029

Adjacent sequences:  A174431 A174432 A174433 * A174435 A174436 A174437

KEYWORD

nonn

AUTHOR

T. D. Noe, Mar 19 2010

STATUS

approved

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Last modified September 27 03:21 EDT 2020. Contains 337380 sequences. (Running on oeis4.)