

A369384


The smallest number k that can be partitioned in n ways as the sum of two numbers from A020487.


1



1, 2, 29, 181, 442, 425, 850, 1300, 2600, 3250, 5525, 11050, 17425, 16900, 44100, 18850, 72250, 44200, 122525, 75400, 55250, 110500, 237250, 188500, 266500, 397800, 375700, 377000, 187850, 221000, 469625, 718250, 640900, 1105000, 1812200, 2340900, 751400, 3591250
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OFFSET

0,2


LINKS



EXAMPLE

a(0) = 1 because 1 cannot be written as the sum of two terms in A020487.
The numbers 3, 4, ..., 28 can be written as the sum of two terms in A020487 in at most one way and 29 = 4 + 25 = A020487(2) + A020487(6) and 29 = 9 + 20 = A020487(3) + A020487(5), so a(2) = 29.


PROG

(Magma) ant:=func<nIsZero(DivisorSigma(2, n) mod DivisorSigma(1, n))>; b:=[n: n in [1..700000] ant(n)]; a:=[]; for n in [0..30] do k:=1; while #RestrictedPartitions(k, 2, Set(b)) ne n do k:=k+1; end while; Append(~a, k); end for; a;


CROSSREFS



KEYWORD

nonn


AUTHOR



EXTENSIONS



STATUS

approved



