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 A227396 Triangle A074909(n) with the first column equal to 1 followed by -A000027(n) instead of A000012. 0
 1, -1, 2, -2, 3, 3, -3, 4, 6, 4, -4, 5, 10, 10, 5, -5, 6, 15, 20, 15, 6, -6, 7, 21, 35, 35, 21, 7, -7, 8, 28, 56, 70, 56, 28, 8, -8, 9, 36, 84, 126, 126, 84, 36, 9, -9, 10, 45, 120, 210, 252, 210, 120, 45, 10, -10 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS Triangle leading to A164555(n)/A027642(n). Starting from B(0)=1, the Bernoulli numbers B(n) with B(1)=1/2 are such that 1*B(0) = 1 -1*B(0) +2*B(1)= 0                               --> B(1)=1/2 -2*B(0) +3*B(1)  +3*B(2) = 0                     --> B(2)=1/6 -3*B(0) +4*B(1)  +6*B(2) +4*B(3) = 0             --> B(3)=0 -4*B(0) +5*B(1) +10*B(2) +10*B(3) +5*B(4) = 0    --> B(4)=-1/30 etc. Row sum of A: A130103(n+1). Row sum's absolute values of A: A145071(n). LINKS FORMULA T(n,k) = A074909(n,k) for n>0 and k>0, T(0,0)=1, T(n,0)=-n for n>0. EXAMPLE a(n) triangle is A: 1 -1 2 -2 3  3 -3 4  6  4 -4 5 10 10  5 -5 6 15 20 15  6 -6 7 21 35 35 21 7  etc. CROSSREFS Sequence in context: A081166 A173910 A036846 * A331590 A326496 A058740 Adjacent sequences:  A227393 A227394 A227395 * A227397 A227398 A227399 KEYWORD sign,tabl AUTHOR Paul Curtz, Sep 20 2013 STATUS approved

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Last modified August 12 17:17 EDT 2020. Contains 336439 sequences. (Running on oeis4.)