A259907 Fifth differences of 7th powers (A001015).
1, 123, 1557, 6719, 16800, 31920, 52080, 77280, 107520, 142800, 183120, 228480, 278880, 334320, 394800, 460320, 530880, 606480, 687120, 772800, 863520, 959280, 1060080, 1165920, 1276800, 1392720, 1513680, 1639680, 1770720, 1906800, 2047920, 2194080, 2345280, 2501520, 2662800
Offset: 0
Examples
1 128 2187 16384 78125 279936 823543 2097152 4782969 (seventh powers) 1 127 2059 14197 61741 201811 543607 1273609 2685817 (first differences) 1 126 1932 12138 47544 140070 341796 730002 1412208 (second differences) 1 125 1806 10206 35406 92526 201726 388206 682206 (third differences) 1 124 1681 8400 25200 57120 109200 186480 294000 (fourth differences) 1 123 1557 6719 16800 31920 52080 77280 107520 (here)
References
- John H. Conway and Richard K. Guy, The Book of Numbers. New York: Springer-Verlag, pp. 30-32, 1996.
- Kiran Parulekar. Amazing Properties of Squares and Their Calculations. Kiran Anil Parulekar, 2012.
- Bag, Amulya Kumar (1966). "Binomial theorem in ancient India". Indian J. History Sci 1 (1): 68-74.
- Ronald Graham and Donald Knuth, Patashnik, Oren (1994). "(5) Binomial Coefficients". Concrete Mathematics (2nd ed.). Addison Wesley. pp. 153-256.
Links
- R. J. Mathar, Table of n, a(n) for n = 0..79
- Index entries for linear recurrences with constant coefficients, signature (3,-3,1).
Programs
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Magma
[1,123,1557,6719] cat [840*(3*n^2-9*n+8): n in [4..40]]; // Bruno Berselli, Jul 16 2015
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Mathematica
Join[{1, 123, 1557, 6719}, Table[840 (3 n^2 - 9 n + 8), {n, 4, 40}]]
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Sage
[1,123,1557,6719]+[840*(3*n^2-9*n+8) for n in (4..40)] # Bruno Berselli, Jul 16 2015
Formula
G.f.: (1 + 120*x + 1191*x^2 + 2416*x^3 + 1191*x^4 + 120*x^5 + x^6)/(1 - x)^3.
a(n) = 840*(3*n^2 - 9*n + 8) for n>3.
a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n>6. - Vincenzo Librandi, Jul 08 2015
Extensions
Edited by Editors of the OEIS, Jul 16 2015