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A053720
Let Py(n)=A000330(n)=n-th square pyramidal number. Consider all integer triples (i,j,k), j >= k>0, with Py(i)=Py(j)+Py(k), ordered by increasing i; sequence gives j values.
2
45, 69, 145, 212, 225, 224, 344, 395, 377, 522, 643, 715, 845, 909, 1082, 1292, 1479, 1547, 1363, 1830, 2290, 2204, 2315, 3017, 3195, 2804, 3293, 4035, 3642, 3394, 4047, 5084, 5309, 5550, 8406, 8631, 8697, 8073, 8728, 9940, 9005, 10804, 10471, 11571
OFFSET
0,1
COMMENTS
i values are A053719 and k values are A053721
EXAMPLE
Py(55) = 56980 = Py(45) + Py(42); Py(70) = 116795 = Py(69) + Py(24);
CROSSREFS
KEYWORD
easy,nice,nonn
AUTHOR
Klaus Strassburger (strass(AT)ddfi.uni-duesseldorf.de), Feb 11 2000
EXTENSIONS
Crossrefs in comments corrected by Jean-François Alcover, Oct 17 2012
STATUS
approved