A272266 The union of squares (A000290) and 10-gonal numbers (A001107).
1, 4, 9, 10, 16, 25, 27, 36, 49, 52, 64, 81, 85, 100, 121, 126, 144, 169, 175, 196, 225, 232, 256, 289, 297, 324, 361, 370, 400, 441, 451, 484, 529, 540, 576, 625, 637, 676, 729, 742, 784, 841, 855, 900, 961, 976, 1024, 1089, 1105, 1156, 1225, 1242, 1296
Offset: 1
Keywords
Links
- Colin Barker, Table of n, a(n) for n = 1..1000
Programs
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PARI
pg(m, n) = (n^2*(m-2)-n*(m-4))/2 \\ The n-th m-gonal number pgr(m, r) = n=1; L=List(); while((t=pg(m, n))
Formula
Conjectures:
a(n) = a(n-1)+2*a(n-3)-2*a(n-4)-a(n-6)+a(n-7) for n>7.
G.f. x*(1+3*x+5*x^2-x^3-x^5+x^6) / ((1-x)^3*(1+x+x^2)^2).