A159389 Number of n X n arrays of squares of integers summing to 13

16, 1962, 350240, 48299450, 5030081280, 346589305664, 14664677168512, 394240010602320, 7283982145272800, 99396267512446410, 1059813625787601696, 9216296747192215226, 67545604711093622960, 427985285624487838800

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

Index entries for linear recurrences with constant coefficients, signature (27, -351, 2925, -17550, 80730, -296010, 888030, -2220075, 4686825, -8436285, 13037895, -17383860, 20058300, -20058300, 17383860, -13037895, 8436285, -4686825, 2220075, -888030, 296010, -80730, 17550, -2925, 351, -27, 1).

Formula

Empirical G.f.: -2*x^2*(1+x)*(8 + 757*x + 150684*x^2 + 19591732*x^3 + 1902144428*x^4 + 111467309309*x^5 + 3357053495448*x^6 + 49669712820552*x^7 + 379085540031904*x^8 + 1572597871783886*x^9 + 3663335172842872*x^10 + 4854870652776840*x^11 + 3663335172842872*x^12 + 1572597871783886*x^13 + 379085540031904*x^14 + 49669712820552*x^15 + 3357053495448*x^16 + 111467309309*x^17 + 1902144428*x^18 + 19591732*x^19 + 150684*x^20 + 757*x^21 + 8*x^22)/(-1+x)^27. - Vaclav Kotesovec, Nov 30 2012

Crossrefs

Sequence in context: A075413 A265213 A176886 * A291828 A086804 A317450

Adjacent sequences: A159386 A159387 A159388 * A159390 A159391 A159392

Keyword

nonn

Author

R. H. Hardin Apr 11 2009

Status

approved