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Numbers that are both 10-gonal numbers (A001107) and 10-gonal pyramidal numbers (A007585).
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%I #33 May 17 2021 08:49:56

%S 0,1,175,368050005576

%N Numbers that are both 10-gonal numbers (A001107) and 10-gonal pyramidal numbers (A007585).

%C Intersection of A001107 and A007585.

%H Numberphile, <a href="https://www.numberphile.com/cannon-ball-numbers">Cannon Ball Numbers</a>.

%o (PARI) for(k=0, 1e4, if(ispolygonal(m=k*(k+1)*(8*k-5)/6, 10), print1(m", ")))

%Y Cf. A001107, A007585, A027568, A344376, A344377.

%K nonn,more

%O 1,3

%A _Seiichi Manyama_, May 17 2021