A077382 - OEIS

A077382

a(1) = 1, then multiply, add and subtract 2, 3, 4; 5, 6, 7; ... in that order.

1, 2, 5, 1, 5, 11, 4, 32, 41, 31, 341, 353, 340, 4760, 4775, 4759, 80903, 80921, 80902, 1618040, 1618061, 1618039, 37214897, 37214921, 37214896, 967587296, 967587323, 967587295, 28060031555, 28060031585, 28060031554, 897921009728

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

LINKS

Table of n, a(n) for n=1..32.

EXAMPLE

a(2) = a(1) *2 = 2, a(3) = a(2) +3= 5, a(4) = a(3) -4 = 1,a(5) = 1*5 = 5, a(6) = a(5)+6 = 11, a(7) = 11-7 = 4, a(8) = 4*8 = 32, etc.

MATHEMATICA

FoldList[If[Mod[#2, 3]==2, #1*#2, If[Mod[#2, 3]==0, #1+#2, #1-#2]]&, 1, Range[2, 32]] (* James C. McMahon, Oct 10 2023 *)

PROG

(Python)

from itertools import count, islice

def A077382_gen(): # generator of terms

yield (a:=1)

for n in count(2, 3):

yield (a:=a*n)

yield (a:=a+n+1)

yield (a:=a-n-2)

A077382_list = list(islice(A077382_gen(), 20)) # Chai Wah Wu, Apr 19 2023

CROSSREFS

Other operation orders: A077383, A077384 A362269, A362270, A362271, A362272.

Sequence in context: A258020 A021803 A356273 * A046527 A008343 A257264

Adjacent sequences: A077379 A077380 A077381 * A077383 A077384 A077385

KEYWORD

nonn

AUTHOR

Amarnath Murthy, Nov 06 2002

EXTENSIONS

More terms from Franklin T. Adams-Watters, May 12 2006

STATUS

approved