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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A009858 Coordination sequence T4 for Zeolite Code -PAR.

Original entry on oeis.org

1, 3, 8, 16, 29, 49, 68, 94, 123, 162, 203, 229, 276, 334, 400, 446, 481, 569, 654, 723, 781, 847, 971, 1064, 1129, 1229, 1331, 1463, 1550, 1645, 1799, 1901, 2041, 2141, 2275, 2469, 2559, 2716, 2847, 3003, 3221, 3324, 3499, 3645, 3828, 4083, 4188, 4380
Offset: 0

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Author

Keywords

References

  • W. M. Meier, D. H. Olson and Ch. Baerlocher, Atlas of Zeolite Structure Types, 4th Ed., Elsevier, 1996.

A009943 Coordination sequence for NiAs(1), As position.

Original entry on oeis.org

1, 6, 24, 56, 96, 152, 216, 296, 384, 488, 600, 728, 864, 1016, 1176, 1352, 1536, 1736, 1944, 2168, 2400, 2648, 2904, 3176, 3456, 3752, 4056, 4376, 4704, 5048, 5400, 5768, 6144, 6536, 6936, 7352, 7776, 8216, 8664, 9128, 9600, 10088, 10584
Offset: 0

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Author

Keywords

References

  • Gmelin Handbook of Inorg. and Organomet. Chem., 8th Ed., 1994, TYPIX search code (194) hP4.

Programs

  • Maple
    (1+4*x+12*x^2+10*x^3-5*x^4+2*x^5)/(1-x^2)/(1-x)^2;

A085690 Number of intersections between a sphere inscribed in a cube and the n X n X n cubes resulting from a cubic lattice subdivision of the enclosing cube.

Original entry on oeis.org

8, 26, 56, 98, 152, 194, 272, 362, 440, 530, 656, 746, 872, 1034, 1160, 1298, 1496, 1658, 1856, 1994, 2240, 2450, 2624, 2906, 3128, 3362, 3656, 3890, 4208, 4442, 4760, 5090, 5360, 5714, 6032, 6362, 6752, 7106, 7496, 7826, 8216, 8618, 9080, 9458, 9896
Offset: 2

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Author

Hugo Pfoertner, Jul 17 2003

Keywords

Comments

A concise description of the problem is given by Clive Tooth in the Seaman, Tooth link. Sequence terms up to n=10 were first given by Dave Seaman. Cubes having at least one vertex on the sphere and all other vertices either all inside or all outside the sphere are counted as 1/2. a(n) is asymptotic to (3/2)*Pi*n^2. (Clive Tooth) The terms a(2),...,a(6) are identical with A005897(n-1) (points on surface of cube with square grid on its faces).

Examples

			a(2)=8 because all 8 cubes resulting from a 2*2*2 subdivision of a cube are intersected by a sphere inscribed in the large cube.
a(4)=56: 8 central cubes of 4*4*4=64 not intersected.
		

Crossrefs

Programs

  • Fortran
    ! See Links.
    (C#) // See Links.

Extensions

Corrected overflow in program and b-file by Hugo Pfoertner, Apr 09 2016

A262067 a(n) = n^n - (n-2)^n.

Original entry on oeis.org

2, 4, 26, 240, 2882, 42560, 745418, 15097600, 347066882, 8926258176, 253930611002, 7916100448256, 268352394448322, 9828088361009152, 386707997366768618, 16268790735900180480, 728714136550643404802, 34624041592426892361728
Offset: 1

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Author

Altug Alkan, Sep 10 2015

Keywords

Comments

Inspired by multi-dimensional cubes: For n>1, the number of lattice points on the surface of a k-dimensional cube with side-length n is f(n,k) = n^k - (n-2)^k. a(n) = f(n,n).

Examples

			For n = 2, a(n) = n^n - (n-2)^n = 2^2 - (2-2)^2 = 4.
		

Crossrefs

For sequences with "Number of points on surface of k-dimensional cube," cf. A130130 (k=1), A008574 (k=2, shifted), A005897 (k=3), A008511 (k=4), A008512 (k=5), A008513 (k=6).

Programs

Formula

a(n) = A000312(n) - A008788(n-2).

A008001 Coordination sequence T1 for Zeolite Code AEI.

Original entry on oeis.org

1, 4, 9, 17, 29, 45, 64, 85, 111, 143, 177, 213, 253, 297, 345, 396, 449, 506, 568, 633, 702, 774, 847, 925, 1008, 1094, 1184, 1276, 1371, 1472, 1577, 1684, 1793, 1906, 2024, 2145, 2269, 2396, 2526, 2660, 2798, 2941, 3088, 3236, 3387, 3544, 3704, 3866, 4032
Offset: 0

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Author

Keywords

References

  • W. M. Meier, D. H. Olson and Ch. Baerlocher, Atlas of Zeolite Structure Types, 4th Ed., Elsevier, 1996

Programs

  • Maple
    (1-x)*(1+7*x^2+13*x^3+22*x^4+33*x^5+45*x^6+57*x^7+71*x^8+85*x^9+
    99*x^10+111*x^11+123*x^12+132*x^13+139*x^14+142*x^15+143*x^16+
    142*x^17+139*x^18+132*x^19+123*x^20+111*x^21+99*x^22+85*x^23+
    71*x^24+3*x+57*x^25+45*x^26+33*x^27+22*x^28+7*x^30+3*x^31+x^32+
    13*x^29)*(x+1)^2/(1-x^3)/(1-x^5)/(1-x^11)/(1-x^16);

A008002 Coordination sequence T2 for Zeolite Code AEI.

Original entry on oeis.org

1, 4, 9, 17, 29, 45, 65, 88, 113, 143, 178, 214, 253, 297, 345, 395, 448, 508, 570, 632, 700, 774, 851, 927, 1007, 1096, 1185, 1275, 1372, 1474, 1577, 1681, 1793, 1910, 2025, 2142, 2267, 2398, 2528, 2660, 2800, 2944, 3088, 3235, 3389, 3546, 3703, 3864, 4031
Offset: 0

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Author

Keywords

References

  • W. M. Meier, D. H. Olson and Ch. Baerlocher, Atlas of Zeolite Structure Types, 4th Ed., Elsevier, 1996

A008003 Coordination sequence T3 for Zeolite Code AEI.

Original entry on oeis.org

1, 4, 9, 17, 29, 45, 65, 87, 113, 143, 176, 214, 253, 297, 345, 395, 451, 507, 568, 634, 700, 772, 848, 928, 1010, 1093, 1184, 1278, 1373, 1472, 1575, 1684, 1793, 1905, 2025, 2146, 2268, 2394, 2528, 2665, 2800, 2940, 3086, 3237, 3388, 3542, 3704, 3867, 4032
Offset: 0

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Author

Keywords

References

  • W. M. Meier, D. H. Olson and Ch. Baerlocher, Atlas of Zeolite Structure Types, 4th Ed., Elsevier, 1996

A008004 Coordination sequence T1 for Zeolite Code AEL.

Original entry on oeis.org

1, 4, 11, 21, 37, 59, 85, 114, 150, 189, 232, 279, 331, 390, 455, 519, 589, 667, 748, 831, 921, 1015, 1115, 1220, 1327, 1439, 1560, 1679, 1802, 1936, 2073, 2213, 2361, 2507, 2659, 2820, 2982, 3150, 3327, 3501, 3681, 3871, 4061, 4254, 4458, 4661, 4868, 5085
Offset: 0

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Author

Keywords

References

  • W. M. Meier, D. H. Olson and Ch. Baerlocher, Atlas of Zeolite Structure Types, 4th Ed., Elsevier, 1996

A008005 Coordination sequence T2 for Zeolite Code AEL.

Original entry on oeis.org

1, 4, 11, 22, 38, 58, 85, 115, 148, 188, 234, 280, 333, 390, 450, 519, 593, 666, 748, 833, 919, 1016, 1118, 1217, 1327, 1441, 1554, 1679, 1810, 1936, 2073, 2213, 2352, 2507, 2667, 2819, 2984, 3153, 3319, 3501, 3688, 3867, 4061, 4258, 4450, 4661, 4878, 5083
Offset: 0

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Author

Keywords

References

  • W. M. Meier, D. H. Olson and Ch. Baerlocher, Atlas of Zeolite Structure Types, 4th Ed., Elsevier, 1996

Formula

G.f.: (1 + 4*x + 11*x^2 + 22*x^3 + 37*x^4 + 54*x^5 + 73*x^6 + 89*x^7 + 99*x^8 + 108*x^9 + 112*x^10 + 111*x^11 + 111*x^12 + 109*x^13 + 106*x^14 + 109*x^15 + 111*x^16 + 111*x^17 + 112*x^18 + 108*x^19 + 99*x^20 + 89*x^21 + 73*x^22 + 54*x^23 + 37*x^24 + 22*x^25 + 11*x^26 + 4*x^27 + x^28) / (1-x^4) / (1-x^6) / (1-x^18). - Sean A. Irvine, Mar 13 2018

A008006 Coordination sequence T3 for Zeolite Code AEL.

Original entry on oeis.org

1, 4, 12, 24, 40, 59, 84, 115, 150, 186, 230, 282, 336, 390, 452, 520, 592, 667, 746, 833, 928, 1018, 1112, 1218, 1328, 1440, 1558, 1678, 1806, 1939, 2072, 2211, 2360, 2508, 2660, 2822, 2986, 3152, 3328, 3502, 3680, 3869, 4060, 4257, 4462, 4660, 4866, 5086
Offset: 0

Views

Author

Keywords

References

  • W. M. Meier, D. H. Olson and Ch. Baerlocher, Atlas of Zeolite Structure Types, 4th Ed., Elsevier, 1996
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