# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a323775 Showing 1-1 of 1 %I A323775 #6 Jan 27 2019 18:03:21 %S A323775 1,3,8,30,359,72385,4338080222,18448597098193762732, %T A323775 340282370354622283774333836315916425069, %U A323775 115792089237316207213755562747271079374483128445080168204415615259394085515423 %N A323775 a(n) = Sum_{k = 1...n} k^(2^(n - k)). %C A323775 Number of ways to choose a constant integer partition of each part of a constant integer partition of 2^(n - 1). %e A323775 The a(1) = 1 through a(4) = 30 twice-partitions: %e A323775 (1) (2) (4) (8) %e A323775 (11) (22) (44) %e A323775 (1)(1) (1111) (2222) %e A323775 (2)(2) (4)(4) %e A323775 (11)(2) (22)(4) %e A323775 (2)(11) (4)(22) %e A323775 (11)(11) (22)(22) %e A323775 (1)(1)(1)(1) (1111)(4) %e A323775 (4)(1111) %e A323775 (11111111) %e A323775 (1111)(22) %e A323775 (22)(1111) %e A323775 (1111)(1111) %e A323775 (2)(2)(2)(2) %e A323775 (11)(2)(2)(2) %e A323775 (2)(11)(2)(2) %e A323775 (2)(2)(11)(2) %e A323775 (2)(2)(2)(11) %e A323775 (11)(11)(2)(2) %e A323775 (11)(2)(11)(2) %e A323775 (11)(2)(2)(11) %e A323775 (2)(11)(11)(2) %e A323775 (2)(11)(2)(11) %e A323775 (2)(2)(11)(11) %e A323775 (11)(11)(11)(2) %e A323775 (11)(11)(2)(11) %e A323775 (11)(2)(11)(11) %e A323775 (2)(11)(11)(11) %e A323775 (11)(11)(11)(11) %e A323775 (1)(1)(1)(1)(1)(1)(1)(1) %t A323775 Table[Sum[k^2^(n-k),{k,n}],{n,12}] %Y A323775 Cf. A000123, A001970, A002577, A006171, A279787, A279789, A305551, A306017, A319056, A323766, A323774, A323776. %K A323775 nonn %O A323775 1,2 %A A323775 _Gus Wiseman_, Jan 27 2019 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE