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A138882 Triangle read by rows: row n lists divisors of n-th even superperfect number A061652(n). 2

%I

%S 1,2,1,2,4,1,2,4,8,16,1,2,4,8,16,32,64,1,2,4,8,16,32,64,128,256,512,

%T 1024,2048,4096,1,2,4,8,16,32,64,128,256,512,1024,2048,4096,8192,

%U 16384,32768,65536,1,2,4,8,16,32,64,128,256,512,1024,2048,4096,8192,16384

%N Triangle read by rows: row n lists divisors of n-th even superperfect number A061652(n).

%C The number of divisors of n-th even superperfect number is equal to A000043(n), then row n has A000043(n) terms.

%C The sum of divisors of n-th even superperfect number is equal to n-th Mersenne prime A000668(n), then n-th row sum is equal to A000668(n).

%H Omar E. Pol, <a href="http://www.polprimos.com">Determinacion geometrica de los numeros primos y perfectos"</a>.

%e Triangle begins:

%e 1, 2

%e 1, 2, 4

%e 1, 2, 4, 8, 16

%e 1, 2, 4, 8, 16, 32, 64

%e 1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096

%e ==============================================================

%e ..... Mersenne ..............................................

%e ....... prime ...............................................

%e n ... A000668(n) = Sum of divisors of A061652(n) .............

%e ==============================================================

%e 1 ........ 3 ... = 1+2

%e 2 ........ 7 ... = 1+2+4

%e 3 ....... 31 ... = 1+2+4+8+16

%e 4 ...... 127 ... = 1+2+4+8+16+32+64

%e 5 ..... 8191 ... = 1+2+4+8+16+32+64+128+256+512+1024+2048+4096

%Y Cf. A000005, A000043, A000203, A000668, A019279, A061652, A133031.

%K nonn,tabf

%O 1,2

%A _Omar E. Pol_, Apr 11 2008

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Last modified July 12 05:35 EDT 2020. Contains 335658 sequences. (Running on oeis4.)