A385624 Antidiagonal sums of the array defined in A385623.

0, 11, 33, 66, 110, 165, 231, 308, 396, 495, 605, 816, 1128, 1541, 2055, 2670, 3386, 4203, 5121, 6140, 7260, 8481, 9803, 11226, 12750, 14375, 16101, 17928, 19856, 21885, 24015, 26246, 28578, 31011, 33545, 36180, 38916, 41753, 44691, 47730, 50870, 54111, 57453, 60896

Offset: 0

Author

Stefano Spezia, Jul 05 2025

Keywords

• nonn
• base

Links

• Stefano Spezia, Table of n, a(n) for n = 0..2000

Crossrefs

Cf. A385623.

Programs

Mathematica

A385623[n_,k_]:=If[k==0,10n,n*10^(Floor[Log10[k]]+1)+k]; a[n_]:=Sum[A385623[n-k,k],{k,0,n}]; Array[a,44,0]

PARI

T(n, k) = if (k==0, 10*n, fromdigits(concat(digits(n), digits(k)))); \\ A385623
a(n) = sum(i=0, n, T(i, n-i)); \\ Michel Marcus, Jul 06 2025