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 A139040 Triangle read by rows: each row is an initial segment of the terms of A000930 followed by its reflection. 2
 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 2, 1, 1, 1, 1, 2, 3, 2, 1, 1, 1, 1, 2, 3, 3, 2, 1, 1, 1, 1, 2, 3, 4, 3, 2, 1, 1, 1, 1, 2, 3, 4, 4, 3, 2, 1, 1, 1, 1, 2, 3, 4, 6, 4, 3, 2, 1, 1, 1, 1, 2, 3, 4, 6, 6, 4, 3, 2, 1, 1, 1, 1, 2, 3, 4, 6, 9, 6, 4, 3, 2, 1, 1, 1, 1, 2, 3, 4, 6, 9, 9, 6, 4, 3, 2, 1, 1 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,13 LINKS G. C. Greubel, Table of n, a(n) for the first 100 rows, flattened EXAMPLE Triangle begins: {1}, {1, 1}, {1, 1, 1}, {1, 1, 1, 1}, {1, 1, 2, 1, 1}, {1, 1, 2, 2, 1, 1}, {1, 1, 2, 3, 2, 1, 1}, {1, 1, 2, 3, 3, 2, 1, 1}, {1, 1, 2, 3, 4, 3, 2, 1, 1}, {1, 1, 2, 3, 4, 4, 3, 2, 1, 1}, {1, 1, 2, 3, 4, 6, 4, 3, 2, 1, 1} MAPLE A000930 := proc(n) coeftayl( 1/(1-x-x^3), x=0, n) ; end: A139040 := proc(n, m) A000930(min(m, n+1-m)) ; end: for n from 1 to 16 do for m from 1 to n do printf("%d, ", A139040(n, m)) ; od: od: # R. J. Mathar, Jun 08 2008 MATHEMATICA a[-2]=0; a[-1]=1; a[0]=1; a[n_]:=a[n]=a[n-1]+a[n-3]; (*A000930*) g[n_, m_]:=If[m <= Floor[n/2], a[m], a[n-m]]; w=Table[Table[g[n, m], {m, 0, n}], {n, 0, 10}]; Flatten[w] CROSSREFS Cf. A139147, A000930. Row sums are in A238383. Sequence in context: A306741 A274193 A238384 * A139147 A055801 A155050 Adjacent sequences:  A139037 A139038 A139039 * A139041 A139042 A139043 KEYWORD nonn,easy,tabl AUTHOR Roger L. Bagula and Gary W. Adamson, May 31 2008 EXTENSIONS Edited and corrected by N. J. A. Sloane, Jun 30 2008 Corrected by Philippe Deléham, Feb 25 2014 STATUS approved

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Last modified January 18 05:18 EST 2021. Contains 340250 sequences. (Running on oeis4.)