login
A135631
Multiples of 31.
13
0, 31, 62, 93, 124, 155, 186, 217, 248, 279, 310, 341, 372, 403, 434, 465, 496, 527, 558, 589, 620, 651, 682, 713, 744, 775, 806, 837, 868, 899, 930, 961, 992, 1023, 1054, 1085, 1116, 1147, 1178, 1209, 1240, 1271, 1302, 1333, 1364, 1395, 1426, 1457, 1488
OFFSET
0,2
COMMENTS
a(1) = 31 is the third Mersenne prime. a(8) = 248 is the dimensions of E_8. a(16) = 496 is the third perfect number. - Pol
a(n)^340 = 155 mod 341 unless a(n) is also divisible by 11. - Alonso del Arte, Feb 15 2012
Number of sides on n triacontakaihenagons (31-gons). - Wesley Ivan Hurt, Oct 25 2016
LINKS
Luis Manuel Rivera, Integer sequences and k-commuting permutations, arXiv preprint arXiv:1406.3081, 2014
FORMULA
a(n) = 31*n.
From G. C. Greubel, Oct 24 2016: (Start)
G.f.: (31*x)/(1 - x)^2.
E.g.f.: 31*x*exp(x).
a(n) = 2*a(n-1) - a(n-2). (End)
EXAMPLE
a(8) = 31 * 8 = 248. a(16) = 31 * 16 = 496.
MAPLE
with(numtheory):a:=proc(n) if n=0 then 0 else mcombine(7*n, 3*n, 5*n, 11*n) fi end: seq(a(n), n=0..45); # Zerinvary Lajos, Apr 11 2008
MATHEMATICA
Range[0, 3000, 31] (* Vladimir Joseph Stephan Orlovsky, Jun 03 2011 *)
LinearRecurrence[{2, -1}, {0, 31}, 25] (* G. C. Greubel, Oct 24 2016 *)
CROSSREFS
Cf. A135628.
Sequence in context: A303698 A164012 A037982 * A276787 A042906 A042904
KEYWORD
easy,nonn
AUTHOR
Omar E. Pol, Nov 25 2007
STATUS
approved