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A243104 Odd numbers in A192274. 1
945, 1575, 2205, 2835, 3465, 4095, 4725, 6435, 6615, 6825, 7245, 7425, 7875, 8085, 8505, 8925, 9135, 9555, 9765, 10395, 11655, 12285, 12915, 13545, 14805, 15015, 16065, 16695, 17955, 18585, 19215, 19635, 19845, 20475, 21105, 21735, 22275, 22365, 22995, 23205 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Chai Wah Wu, Table of n, a(n) for n = 1..500

PROG

(Python)

from sympy import divisors

import numpy as np

A243104 = []

for n in range(3, 10**4, 2):

....d = divisors(n)

....s = sum(d)

....if not s % 2 and 2*n <= s:

........d.remove(n)

........s2, ld = int(s/2-n), len(d)

........z = np.zeros((ld+1, s2+1), dtype=int)

........for i in range(1, ld+1):

............y = min(d[i-1], s2+1)

............z[i, range(y)] = z[i-1, range(y)]

............z[i, range(y, s2+1)] = np.maximum(z[i-1, range(y, s2+1)], z[i-1, range(0, s2+1-y)]+y)

............if z[i, s2] == s2:

................d2 = [2*x for x in d if n > 2*x and n % (2*x)] + \

................[x for x in divisors(2*n-1) if n > x >=2 and n % x] + \

................[x for x in divisors(2*n+1) if n > x >=2 and n % x]

................s, dmax = sum(d2), max(d2)

................if not s % 2 and 2*dmax <= s:

....................d2.remove(dmax)

....................s2, ld = int(s/2-dmax), len(d2)

....................z = np.zeros((ld+1, s2+1), dtype=int)

....................for i in range(1, ld+1):

........................y = min(d2[i-1], s2+1)

........................z[i, range(y)] = z[i-1, range(y)]

........................z[i, range(y, s2+1)] = np.maximum(z[i-1, range(y, s2+1)], z[i-1, range(0, s2+1-y)]+y)

........................if z[i, s2] == s2:

............................A243104.append(n)

............................break

................break

CROSSREFS

Cf. A192274.

Sequence in context: A005231 A174865 A174535 * A006038 A287646 A316116

Adjacent sequences:  A243101 A243102 A243103 * A243105 A243106 A243107

KEYWORD

nonn

AUTHOR

Chai Wah Wu, Aug 19 2014

STATUS

approved

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Last modified August 22 20:47 EDT 2019. Contains 326209 sequences. (Running on oeis4.)