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A034297
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Number of ordered positive integer solutions (m_1, m_2, ..., m_k) (for some k) to Sum_{i=1..k} m_i=n with |m_i-m_{i-1}| <= 1 for i = 2 ... k.
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3
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1, 2, 4, 6, 11, 17, 29, 47, 78, 130, 215, 357, 595, 990, 1651, 2748, 4584, 7643, 12744, 21256, 35451, 59133, 98636, 164531, 274463, 457837, 763746, 1274060, 2125356, 3545491, 5914545, 9866602, 16459421, 27457549, 45804648, 76411272, 127469285
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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PROG
| (PARI) T = matrix(70, 70, i, j, -1); doIt(last, left) = local(c); c = T[last, left]; if (c == -1, c = 0; for (i = max(1, last - 1), last + 1, c += b(i, left - i)); T[last, left] = c); c; b(last, left) = if (left == 0, return(1)); if (left < 0, return(0)); doIt(last, left); a(n) = sum (i = 1, n, b(i, n - i)); (Wasserman)
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CROSSREFS
| Cf. A003116, A034296.
Sequence in context: A115315 A004698 A014217 * A026636 A026658 A138688
Adjacent sequences: A034294 A034295 A034296 * A034298 A034299 A034300
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KEYWORD
| nonn
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AUTHOR
| Erich Friedman (erich.friedman(AT)stetson.edu)
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EXTENSIONS
| More terms from David Wasserman (wasserma(AT)spawar.navy.mil), Feb 02 2006
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