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 A342824 Number of ways n appears as a cross-polytope number (A142978). 0
 1, 1, 2, 1, 2, 1, 2, 2, 2, 1, 2, 1, 2, 1, 3, 1, 2, 2, 2, 1, 2, 1, 2, 2, 2, 1, 2, 1, 2, 1, 2, 2, 2, 1, 3, 1, 2, 1, 2, 1, 2, 1, 3, 1, 2, 1, 2, 2, 2, 2, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 3, 1, 2, 1, 2, 1, 2, 1, 2, 2, 2, 1, 2, 1, 2, 1, 2, 2, 2, 1, 2, 2, 2, 1, 2 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,3 COMMENTS Every entry in the first column (of A142978) is 1, so this sequence starts at a(2). a(n) is always positive, as the first row lists the positive integers. a(n) >= 3 infinitely often. This happens, in particular, at every even square > 4. (The second row contains the squares, and the second column the positive even numbers.) For n <= 10000, the only instance of a(n) > 3 is a(1156) = 4. This occurs because 1156 is even, square, and octahedral (third row of A142978). LINKS PROG (Sage) def a(n) : return len([K for K in [2..n] if n == next(A142978(N, K) for N in (1..) if A142978(N, K) >= n)]) CROSSREFS Cf. A142978. Sequence in context: A071854 A183025 A072410 * A072491 A051034 A024935 Adjacent sequences:  A342821 A342822 A342823 * A342825 A342826 A342827 KEYWORD nonn AUTHOR Eric M. Schmidt, Mar 22 2021 STATUS approved

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Last modified May 8 18:28 EDT 2021. Contains 343666 sequences. (Running on oeis4.)