cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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A079963 Number of permutations satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..n, with k=1, r=5, I={1,2}.

Original entry on oeis.org

1, 1, 1, 1, 2, 4, 7, 10, 14, 21, 34, 55, 86, 131, 200, 310, 485, 757, 1174, 1815, 2810, 4362, 6778, 10524, 16323, 25310, 39260, 60924, 94549, 146706, 227599, 353093, 547826, 850005, 1318859, 2046257, 3174775, 4925699, 7642389, 11857510
Offset: 0

Views

Author

Vladimir Baltic, Feb 19 2003

Keywords

Comments

Number of compositions (ordered partitions) of n into elements of the set {1,4,5,6}.

References

  • D. H. Lehmer, Permutations with strongly restricted displacements. Combinatorial theory and its applications, II (Proc. Colloq., Balatonfured, 1969), pp. 755-770. North-Holland, Amsterdam, 1970.

Crossrefs

Formula

a(n) = a(n-1)+a(n-4)+a(n-5)+a(n-6).
G.f.: -1/(x^6+x^5+x^4+x-1).

A079964 Number of permutations satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..n, with k=1, r=5, I={0,4}.

Original entry on oeis.org

1, 0, 1, 1, 2, 2, 5, 5, 10, 13, 22, 30, 50, 70, 112, 163, 254, 375, 579, 862, 1320, 1979, 3015, 4536, 6893, 10392, 15764, 23800, 36064, 54492, 82521, 124748, 188841, 285561, 432174, 653642, 989097, 1496125, 2263754, 3424425, 5181150, 7837946
Offset: 0

Views

Author

Vladimir Baltic, Feb 19 2003

Keywords

Comments

Number of compositions (ordered partitions) of n into elements of the set {2,3,4,6}.

References

  • D. H. Lehmer, Permutations with strongly restricted displacements. Combinatorial theory and its applications, II (Proc. Colloq., Balatonfured, 1969), pp. 755-770. North-Holland, Amsterdam, 1970.

Crossrefs

Formula

a(n) = a(n-2)+a(n-3)+a(n-4)+a(n-6).
G.f.: -1/(x^6+x^4+x^3+x^2-1).

A079965 Number of permutations satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..n, with k=1, r=5, I={0,3}.

Original entry on oeis.org

1, 0, 1, 1, 1, 3, 3, 5, 8, 10, 17, 24, 35, 54, 77, 116, 172, 252, 377, 555, 822, 1220, 1801, 2671, 3953, 5849, 8666, 12823, 18987, 28113, 41612, 61615, 91214, 135037, 199929, 295976, 438193, 648734, 960420, 1421893, 2105059, 3116482, 4613879, 6830695
Offset: 0

Views

Author

Vladimir Baltic, Feb 19 2003

Keywords

Comments

Number of compositions (ordered partitions) of n into elements of the set {2,3,5,6}.

References

  • D. H. Lehmer, Permutations with strongly restricted displacements. Combinatorial theory and its applications, II (Proc. Colloq., Balatonfured, 1969), pp. 755-770. North-Holland, Amsterdam, 1970.

Crossrefs

Programs

  • Mathematica
    LinearRecurrence[{0,1,1,0,1,1},{1,0,1,1,1,3},50] (* Harvey P. Dale, Jul 10 2017 *)

Formula

a(n) = a(n-2)+a(n-3)+a(n-5)+a(n-6).
G.f.: -1/(x^6+x^5+x^3+x^2-1).

A079966 Number of permutations satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..n, with k=1, r=5, I={0,2}.

Original entry on oeis.org

1, 0, 1, 0, 2, 1, 4, 2, 7, 5, 14, 12, 27, 26, 53, 57, 106, 122, 212, 258, 428, 543, 868, 1135, 1766, 2364, 3605, 4910, 7374, 10175, 15109, 21054, 30998, 43513, 63656, 89851, 130817, 185416, 268984, 382436, 553308, 788520, 1138525, 1625356, 2343253
Offset: 0

Views

Author

Vladimir Baltic, Feb 19 2003

Keywords

Comments

Number of compositions (ordered partitions) of n into elements of the set {2,4,5,6}.

References

  • D. H. Lehmer, Permutations with strongly restricted displacements. Combinatorial theory and its applications, II (Proc. Colloq., Balatonfured, 1969), pp. 755-770. North-Holland, Amsterdam, 1970.

Crossrefs

Formula

a(n) = a(n-2)+a(n-4)+a(n-5)+a(n-6).
G.f.: -1/(x^6+x^5+x^4+x^2-1).

A079967 Number of permutations satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..n, with k=1, r=5, I={4}.

Original entry on oeis.org

1, 1, 2, 4, 8, 15, 30, 58, 113, 220, 429, 835, 1627, 3169, 6173, 12024, 23422, 45623, 88869, 173107, 337194, 656817, 1279409, 2492150, 4854439, 9455922, 18419114, 35878442, 69887326, 136132954, 265172275, 516526919, 1006138588, 1959849178
Offset: 0

Views

Author

Vladimir Baltic, Feb 19 2003

Keywords

Comments

Number of compositions (ordered partitions) of n into elements of the set {1,2,3,4,6}.
Note that the number of compositions of n with parts in N which avoid the pattern 221 (see Heubach/Mansour) is not this sequence but A134044.

References

  • D. H. Lehmer, Permutations with strongly restricted displacements. Combinatorial theory and its applications, II (Proc. Colloq., Balatonfured, 1969), pp. 755-770. North-Holland, Amsterdam, 1970.

Crossrefs

Formula

a(n) = a(n-1)+a(n-2)+a(n-3)+a(n-4)+a(n-6).
G.f.: -1/(x^6+x^4+x^3+x^2+x-1).

A079969 Number of permutations satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..n, with k=1, r=5, I={2}.

Original entry on oeis.org

1, 1, 2, 3, 6, 11, 21, 38, 70, 128, 236, 434, 799, 1469, 2702, 4969, 9140, 16811, 30921, 56872, 104604, 192396, 353872, 650872, 1197141, 2201885, 4049898, 7448923, 13700706, 25199527, 46349157, 85249390, 156798074, 288396620, 530444084
Offset: 0

Views

Author

Vladimir Baltic, Feb 19 2003

Keywords

Comments

Number of compositions (ordered partitions) of n into elements of the set {1,2,4,5,6}.

References

  • D. H. Lehmer, Permutations with strongly restricted displacements. Combinatorial theory and its applications, II (Proc. Colloq., Balatonfured, 1969), pp. 755-770. North-Holland, Amsterdam, 1970.

Crossrefs

Programs

  • Mathematica
    LinearRecurrence[{1,1,0,1,1,1},{1,1,2,3,6,11},40] (* Harvey P. Dale, Aug 03 2014 *)

Formula

a(n) = a(n-1)+a(n-2)+a(n-4)+a(n-5)+a(n-6).
G.f.: -1/(x^6+x^5+x^4+x^2+x-1).

A079995 Number of permutations satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..n, with k=3, r=3, I={2}.

Original entry on oeis.org

1, 1, 2, 4, 14, 39, 103, 255, 665, 1741, 4605, 12046, 31474, 82206, 215157, 563083, 1473635, 3855111, 10085589, 26386595, 69038554, 180630858, 472594580, 1236463719, 3235013481, 8463923170, 22144596592, 57937977232, 151585883920
Offset: 0

Views

Author

Vladimir Baltic, Feb 17 2003

Keywords

Comments

Also, number of permutations satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..n, with k=3, r=3, I={-2}.

References

  • D. H. Lehmer, Permutations with strongly restricted displacements. Combinatorial theory and its applications, II (Proc. Colloq., Balatonfured, 1969), pp. 755-770. North-Holland, Amsterdam, 1970.

Crossrefs

Programs

  • Mathematica
    CoefficientList[Series[-(x^14-x^12+x^11-x^10-x^9-x^8+3x^6-x^5+ x^4+ 3x^3+ x^2-1)/ (x^20+ x^19-2x^18+ x^17+4x^16-4x^15-9x^14- 3x^13+ 11x^12+ x^11- 5x^10+ 7x^9+11x^8+9x^7-13x^6-6x^5-4x^4-3x^3-2x^2-x+1),{x,0,40}],x] (* or *) LinearRecurrence[{1,2,3,4,6,13,-9,-11,-7,5,-1,-11,3,9,4,-4,-1,2,-1,-1},{1,1,2,4,14,39,103,255,665,1741,4605,12046, 31474,82206,215157, 563083, 1473635,3855111,10085589,26386595},40] (* Harvey P. Dale, Oct 29 2017 *)

Formula

a(n) = a(n-1) +2*a(n-2) +3*a(n-3) +4*a(n-4) +6*a(n-5) +13*a(n-6) -9*a(n-7) -11*a(n-8) -7*a(n-9) +5*a(n-10) -a(n-11) -11*a(n-12) +3*a(n-13) +9*a(n-14) +4*a(n-15) -4*a(n-16) -a(n-17) +2*a(n-18) -a(n-19) -a(n-20).
G.f.: -(x^14 -x^12 +x^11 -x^10 -x^9 -x^8 +3*x^6 -x^5 +x^4 +3*x^3 +x^2-1)/ (x^20 +x^19 -2*x^18 +x^17 +4*x^16 -4*x^15 -9*x^14 -3*x^13 +11*x^12 +x^11 -5*x^10 +7*x^9 +11*x^8 +9*x^7 -13*x^6 -6*x^5 -4*x^4 -3*x^3 -2*x^2 -x+1)
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