A159401 Number of n X n arrays of squares of integers summing to 18.

30, 4656, 1785640, 620034300, 186034854330, 41535948202896, 6215087324054848, 583572966788128320, 34534249243423434450, 1358435234100803814340, 37831746939409059248040, 788796221709817955804040, 12886433906907110589156390, 171056501049470927711917200

Offset

2,1

Comments

All such sequences have holonomic recurrences (cf. comment in A159359). - Georg Fischer, Feb 17 2022

Links

R. H. Hardin, Table of n, a(n) for n = 2..100

Vaclav Kotesovec, G.f. for A159401

Index entries for linear recurrences with constant coefficients, signature (37, -666, 7770, -66045, 435897, -2324784, 10295472, -38608020, 124403620, -348330136, 854992152, -1852482996, 3562467300, -6107086800, 9364199760, -12875774670, 15905368710, -17672631900, 17672631900, -15905368710, 12875774670, -9364199760, 6107086800, -3562467300, 1852482996, -854992152, 348330136, -124403620, 38608020, -10295472, 2324784, -435897, 66045, -7770, 666, -37, 1).

Formula

G.f.: see link above. - Vaclav Kotesovec, Dec 04 2012

Crossrefs

Sequence in context: A246620 A216728 A196466 * A288033 A341875 A204975

Adjacent sequences: A159398 A159399 A159400 * A159402 A159403 A159404

Keyword

nonn

Author

R. H. Hardin, Apr 11 2009

Status

approved