A248473 -id:A248473 - cp's OEIS frontend

A249388 Put a [+] b = A(A(a) + A(b)), where A=A007913. The sequence lists consecutive row "sums" of triangle A248473, using [+].

1, 2, 1, 2, 3, 2, 2, 94, 1, 1, 1, 2, 6, 2, 17, 2, 2, 1187, 6, 2, 1, 62, 2, 56883, 14, 3, 14471, 2, 14, 3018, 34, 6, 3, 29, 67, 19, 1, 38, 528846, 9758, 14, 18278015, 163506530, 767014, 7, 2, 2611563, 2081053770, 3, 2, 2, 53654, 94, 17175330570, 2, 1612685866

Offset: 0

Vladimir Shevelev and Peter J. C. Moses, Oct 27 2014

nonn

Cf. A007913, A248470, A248473.

a7913[n_]:=a7913[n]=Times@@(#[[1]]^Mod[#[[2]],2])&[Transpose[FactorInteger[n]]];
ab[x_,y_]:=ab[x,y]=a7913[a7913[x]+a7913[y]];
Map[Fold[ab,First[#],Rest[#]]&,Table[a7913[Binomial[a7913[m],a7913[k]]],{m,0,50},{k,0,m}]] (* Peter J. C. Moses, Oct 27 2014 *)

A249416 a(n) = core(Sum_{i=0,...,n} core(binomial(n,i))), where core(n) = A007913(n).

Original entry on oeis.org

1, 2, 1, 2, 10, 2, 1, 2, 118, 19, 519, 2, 635, 370, 829, 1333, 8454, 17315, 3599, 15307, 423769, 852006, 495431, 2, 2425755, 2121070, 3192295, 1614598, 35685686, 10081687, 735961, 12902173, 216093318, 151123623, 5270424935, 39937013, 22884337, 7281379334

Offset: 0

Vladimir Shevelev, Oct 28 2014

nonn

Cf. A007913, A248470, A248473, A249388.

a7913[n_]:=a7913[n]=Times@@(#[[1]]^Mod[#[[2]],2])&[Transpose[FactorInteger[n]]];
Map[a7913[Total[Map[a7913,Binomial[#,Range[0,#]]]]]&,Range[0,50]] (* Peter J. C. Moses, Oct 28 2014 *)

a(n) = core(sum(i=0, n, core(binomial(n,i)))); \\ Michel Marcus, Nov 13 2014

More terms from Peter J. C. Moses, Oct 28 2014

cp's OEIS Frontend

A249388 Put a [+] b = A(A(a) + A(b)), where A=A007913. The sequence lists consecutive row "sums" of triangle A248473, using [+].

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