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A008228
Coordination sequence T2 for Zeolite Code PHI.
1
1, 4, 9, 18, 32, 48, 68, 96, 126, 155, 191, 234, 277, 322, 373, 429, 490, 555, 620, 688, 765, 845, 923, 1007, 1099, 1192, 1289, 1395, 1500, 1602, 1716, 1838, 1954, 2073, 2203, 2336, 2473, 2617, 2757, 2897, 3053, 3212, 3362, 3521, 3692, 3861, 4035, 4220
OFFSET
0,2
COMMENTS
Also coordination sequence T3 for zeolite code SIV. - Sean A. Irvine, Mar 19 2018
REFERENCES
W. M. Meier, D. H. Olson and Ch. Baerlocher, Atlas of Zeolite Structure Types, 4th Ed., Elsevier, 1996
FORMULA
G.f.: (1 + x) * (1 + x + 4*x^2 + 5*x^3 + 9*x^4 + 10*x^5 + 16*x^6 + 16*x^7 + 22*x^8 + 21*x^9 + 26*x^10 + 24*x^11 + 26*x^12 + 21*x^13 + 22*x^14 + 16*x^15 + 16*x^16 + 10*x^17 + 9*x^18 + 5*x^19 + 4*x^20 + x^21 + x^22) / ((1 - x)^3 * (1 + x^2) * (1 + x + x^2) * (1 - x + x^2 - x^3 + x^4)^2 * (1 + x + x^2 + x^3 + x^4)^2). - Colin Barker, Dec 20 2015
G.f.: (1 + 4*x + 35*x^5 + 41*x^6 + 47*x^7 + 9*x^2 + 17*x^3 + 27*x^4 + 50*x^8 + 48*x^9 + 43*x^10 + 36*x^11 + 26*x^12 + 10*x^13 - 10*x^14 - 26*x^15 - 36*x^16 - 43*x^17 - 48*x^18 - 50*x^19 - 47*x^20 - 41*x^21 - 35*x^22 - 27*x^23 - 17*x^24 - 9*x^25 - 4*x^26 - x^27) / (1 - x^3) / (1 - x^4) / (1 - x^10)^2. - Sean A. Irvine, Mar 14 2018
CROSSREFS
Sequence in context: A008266 A301200 A008222 * A008160 A301201 A301199
KEYWORD
nonn
STATUS
approved