A048202 a(n)=T(n,2), array T given by A048201.

3, 6, 9, 13, 18, 24, 29, 31, 37, 43, 47, 51, 54, 61, 67, 69, 71, 74, 78, 82, 88, 94, 97, 99, 103, 110, 117, 122, 126, 129, 135, 147, 157, 161, 164, 168, 171, 176, 181, 183, 192, 204, 211, 215, 224, 235, 243, 251, 259, 265, 270, 278

Offset

2,1

Links

Chai Wah Wu, Table of n, a(n) for n = 2..10000

Formula

a(n) = A002048(n) + A002048(n+1). [Gerald Hillier, Oct 04 2008]

Prog

(Python)
from itertools import count, accumulate, islice
from collections import deque
def A048202_gen(): # generator of terms
    aset, alist = {1}, deque([1])
    for k in count(2):
        if k in aset:
            aset.remove(k)
        else:
            yield k+alist[0]
            aset |= set(k+d for d in accumulate(alist))
            alist.appendleft(k)
A048202_list = (list(islice(A048202_gen(), 52))) # Chai Wah Wu, Sep 02 2025

Crossrefs

Cf. A048201, A002048.

Sequence in context: A092847 A143975 A005488 * A014785 A132352 A033436

Adjacent sequences: A048199 A048200 A048201 * A048203 A048204 A048205

Keyword

nonn

Author

Clark Kimberling

Status

approved