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 A247936 Riordan array ((1-2x)/(1-3x), 2x). 0
 1, 1, 2, 3, 2, 4, 9, 6, 4, 8, 27, 18, 12, 8, 16, 81, 54, 36, 24, 16, 32, 243, 162, 108, 72, 48, 32, 64, 729, 486, 324, 216, 144, 96, 64, 128, 2187, 1458, 972, 648, 432, 288, 192, 128, 256, 6561, 4374, 2916, 1944, 1296, 864, 576, 384, 256, 512, 19683, 13122 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS Mirror of A153279. LINKS FORMULA Sum_{k, 0<=k<=n} T(n,k) = 3^n = A000244(n). T(n,k) = A133494(n-k)*2^k. T(2n,n) = A167747(n). EXAMPLE Triangle begins: 1 1, 2 3, 2, 4 9, 6, 4, 8 27, 18, 12, 8, 16 81, 54, 36, 24, 16, 32 243, 162, 108, 72, 48, 32, 64 Production matrix begins: 1, 2 1, 0, 2 1, 0, 0, 2 1, 0, 0, 0, 2 1, 0, 0, 0, 0, 2 1, 0, 0, 0, 0, 0, 2 1, 0, 0, 0, 0, 0, 0, 2 CROSSREFS Cf. A000079, A000244, A133494, A153279, A167747. Sequence in context: A059576 A274803 A274749 * A231150 A274858 A207997 Adjacent sequences:  A247933 A247934 A247935 * A247937 A247938 A247939 KEYWORD nonn,tabl AUTHOR Philippe Deléham, Sep 26 2014 STATUS approved

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Last modified August 5 18:00 EDT 2021. Contains 346488 sequences. (Running on oeis4.)