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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 February 20 19:02 EST 2020. Contains 332082 sequences. (Running on oeis4.)