A065525 The (6^n)-th composite number.

4, 12, 52, 275, 1539, 8883, 51974, 306464, 1815791, 10791313, 64266028, 383289080, 2288430270, 13674181949, 81759268145, 489087871679, 2926904894187, 17521456528700, 104917324472297, 628377368081285, 3764220848092978, 22552713068921032, 135139349515525416

Offset

0,1

Links

Table of n, a(n) for n=0..22.

Formula

a[n] = PrimePi[a[n]]+6^n+1.

Example

a[4] = 1539 = PrimePi[1539]+6^4+1 = 242+1296+1.

Mathematica

Composite[n_Integer] := Block[ {k = n + PrimePi[n] + 1 }, While[ k != n + PrimePi[k] + 1, k = n + PrimePi[k] + 1]; Return[ k ]]; Table[ Composite[6^n], {n, 0, 17} ]

Crossrefs

Sequence in context: A034716 A129841 A277431 * A317281 A190342 A262745

Adjacent sequences: A065522 A065523 A065524 * A065526 A065527 A065528

Keyword

nonn

Author

Robert G. Wilson v, Nov 27 2001

Extensions

Corrected by Vladeta Jovovic, Dec 10 2001

a(18)-a(22) from Chai Wah Wu, Apr 21 2018

Status

approved