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 A277239 Number A(n,k) of factorizations of m^n into exactly k factors, where m is a product of two distinct primes; square array A(n,k), n>=0, k>=0, read by antidiagonals. 11
 1, 1, 0, 1, 1, 0, 1, 2, 1, 0, 1, 2, 5, 1, 0, 1, 2, 8, 8, 1, 0, 1, 2, 9, 19, 13, 1, 0, 1, 2, 9, 27, 42, 18, 1, 0, 1, 2, 9, 30, 74, 78, 25, 1, 0, 1, 2, 9, 31, 95, 168, 139, 32, 1, 0, 1, 2, 9, 31, 105, 248, 363, 224, 41, 1, 0, 1, 2, 9, 31, 108, 300, 614, 703, 350, 50, 1, 0 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,8 LINKS Alois P. Heinz, Antidiagonals n = 0..45, flattened EXAMPLE Square array A(n,k) begins:   1, 1,  1,   1,    1,    1,    1,    1,    1, ...   0, 1,  2,   2,    2,    2,    2,    2,    2, ...   0, 1,  5,   8,    9,    9,    9,    9,    9, ...   0, 1,  8,  19,   27,   30,   31,   31,   31, ...   0, 1, 13,  42,   74,   95,  105,  108,  109, ...   0, 1, 18,  78,  168,  248,  300,  325,  335, ...   0, 1, 25, 139,  363,  614,  814,  938, 1002, ...   0, 1, 32, 224,  703, 1367, 1996, 2457, 2741, ...   0, 1, 41, 350, 1297, 2879, 4642, 6128, 7168, ... CROSSREFS Columns k=0-10 give: A000007, A000012, A000982(n+1), A101427, A277240, A277241, A277242, A277243, A277244, A277245, A277246. Main diagonal gives A254686. A(n,2n) gives A002774. Sequence in context: A145895 A114503 A103528 * A138352 A129620 A074766 Adjacent sequences:  A277236 A277237 A277238 * A277240 A277241 A277242 KEYWORD nonn,tabl AUTHOR Alois P. Heinz, Oct 06 2016 STATUS approved

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Last modified July 18 01:05 EDT 2019. Contains 325109 sequences. (Running on oeis4.)