A138728 Array read by rows: row n lists n-th even superperfect number A061652(n), n-th Mersenne prime A000668(n) and n-th perfect number A000396(n).

2, 3, 6, 4, 7, 28, 16, 31, 496, 64, 127, 8128, 4096, 8191, 33550336, 65536, 131071, 8589869056, 262144, 524287, 137438691328, 1073741824, 2147483647, 2305843008139952128, 1152921504606846976, 2305843009213693951

Offset

1,1

Links

Table of n, a(n) for n=1..26.

L. C. Noll, Mersenne Prime Digits and Names.

J. M. Pedersen, Known Perfect Numbers.

Omar E. Pol, Determinacion geometrica de los numeros primos y perfectos.

Example

Array begins:
2, 3, 6
4, 7, 28
16, 31, 496

Crossrefs

Cf. A000396, A000668, A019279, A061652, A138818, A138819.

Sequence in context: A273338 A099900 A193903 * A291604 A082332 A154285

Adjacent sequences: A138725 A138726 A138727 * A138729 A138730 A138731

Keyword

nonn,tabf

Author

Omar E. Pol, Apr 07 2008

Status

approved