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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A026971 Self-convolution of array T given by A026648.

Original entry on oeis.org

1, 2, 11, 34, 138, 492, 2342, 8500, 39814, 148124, 709266, 2665932, 12824196, 48623448, 235400988, 897705096, 4362689862, 16713200556, 81488683874, 313281535180, 1531312911148, 5903966489576, 28918583700468, 111757786454424, 548352142452124, 2123323536391448
Offset: 0

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More terms from Sean A. Irvine, Oct 20 2019

A026972 a(n) = Sum_{k=0..n-1} T(n,k) * T(n,k+1), with T given by A026648.

Original entry on oeis.org

1, 6, 24, 108, 406, 1908, 7289, 34248, 131766, 623700, 2416836, 11487528, 44745468, 213451560, 834897375, 3993910416, 15673923910, 75152083716, 295737641768, 1420670333640, 5603322265428, 26960309526744, 106539505068194, 513309625743600, 2031786103702780, 9800639852315208
Offset: 1

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More terms from Sean A. Irvine, Oct 20 2019

A026973 a(n) = Sum_{k=0..n-2} T(n,k) * T(n,k+2), with T given by A026648.

Original entry on oeis.org

1, 8, 52, 224, 1131, 4620, 23456, 92752, 460170, 1805760, 8946216, 34942176, 172593267, 673129380, 3323413216, 12954246368, 63944790462, 249263001360, 1230668687000, 4798770328960, 23700302314238, 92457112946968, 456814709763456, 1782991313610720, 8813232700137268
Offset: 2

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More terms from Sean A. Irvine, Oct 20 2019

A026974 a(n) = Sum_{k=0..n-3} T(n,k) * T(n,k+3), with T given by A026648.

Original entry on oeis.org

1, 12, 77, 450, 2154, 11592, 51060, 261720, 1106790, 5562216, 23051943, 114491286, 468950860, 2313509520, 9409147640, 46221336720, 187136146566, 916762621320, 3700703183930, 18096198791748, 72903667955404, 356052268340208, 1432473805470840, 6990085402419600, 28096469154731484
Offset: 3

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More terms from Sean A. Irvine, Oct 20 2019

A026975 a(n) = Sum_{k=0..n} (k+1) * A026648(n,k).

Original entry on oeis.org

1, 3, 10, 25, 66, 154, 392, 882, 2180, 4796, 11640, 25220, 60424, 129480, 307264, 652936, 1538064, 3247024, 7604000, 15968400, 37217312, 77818016, 180652416, 376359200, 870795328, 1808574912, 4172640640, 8643327040
Offset: 0

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Conjectures from Colin Barker, Feb 18 2016: (Start)
a(n) = 8*a(n-2)-12*a(n-4)-16*a(n-6)-4*a(n-8) for n>7.
G.f.: (1+3*x+2*x^2+x^3-2*x^4-10*x^5-2*x^7) / (1-4*x^2-2*x^4)^2.
(End)
Previous Showing 11-15 of 15 results.