A202303 Drop the last digit of A023110(n).

0, 0, 0, 0, 1, 4, 16, 25, 36, 144, 324, 1849, 6400, 23716, 36481, 51984, 207936, 467856, 2666689, 9229444, 34199104, 52606009, 74960964, 299843856, 674648676, 3845364121, 13308852496, 49315084900, 75857828929, 108093658176, 432374632704, 972842923584, 5545012396225, 19191356070436, 71112318227344, 109386936710041, 155870980128900, 623483920515600, 1402838821160100

Offset: 1

Author

N. J. A. Sloane, Jan 12 2012

Keywords

• nonn
• base

Comments

By definition, all the terms are squares.

References

• R. K. Guy, Neg and Reg, preprint, Jan 2012.

Crossrefs

Cf. A023110. The square roots are in A031150.

Formula

Conjecture: a(n) = 1443*a(n-7)-1443*a(n-14)+a(n-21). - Colin Barker, Sep 20 2014

Empirical g.f.: -x^5*(x +1)*(x^16 +3*x^15 +13*x^14 +12*x^13 +312*x^12 -168*x^11 +204*x^10 +202*x^9 +426*x^8 +202*x^7 +204*x^6 +120*x^5 +24*x^4 +12*x^3 +13*x^2 +3*x +1) / ((x -1)*(x^6 +x^5 +x^4 +x^3 +x^2 +x +1)*(x^14 -1442*x^7 +1)). - Colin Barker, Sep 20 2014

Extensions

Fourth leading 0 inserted by Georg Fischer, Feb 21 2022