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A139369 Array read by antidiagonals, n-th sum of 2 distinct powers of k. 0
3, 4, 5, 5, 10, 6, 6, 17, 12, 9, 7, 26, 20, 28, 10, 8, 37, 30, 65, 30, 12, 9, 50, 42, 126, 68, 36, 17, 10, 65, 56, 217, 130, 80, 82, 18, 11, 82, 72, 344, 222, 150, 257, 84, 20, 12, 101, 90, 513, 350, 252, 626, 260, 90, 24, 13, 122, 110, 730, 520, 392, 1297, 630, 272, 108 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

n=2 column is A002522 n^2 + 1.

n=3 column is A002378 n*(n+1) Oblong (or pronic, promic, or heteromecic numbers).

LINKS

Table of n, a(n) for n=1..65.

EXAMPLE

Array begins:

================================================================================

k....|.n=1.|.n=2.|.n=3.|..n=4.|..n=5.|..n=6.|...n=7.|...n=8.|..n=9.|.n=10|.OEIS.

================================================================================

k=2..|..3..|...5.|..6..|....9.|...10.|...12.|....17.|...18..|...20.|..24.|A018900

k=3..|..4..|..10.|.12..|...28.|...30.|...36.|....82.|...84..|...90.|..108|A038464

k=4..|..5..|..17.|.20..|...65.|...68.|...80.|...257.|..260..|..272.|..320|A038470

k=5..|..6..|..26.|.30..|..126.|..130.|..150.|...626.|..630..|..650.|..750|A038474

k=6..|..7..|..37.|.42..|..217.|..222.|..252.|..1297.|..1302.|.1332.|.1512|A038478

k=7..|..8..|..50.|.56..|..344.|..350.|..392.|..2402.|..2408.|.2450.|.2744|A038481

k=8..|..9..|..65.|.72..|..513.|..520.|..576.|..4097.|..4104.|.4160.|.4608|A038484

k=9..|.10..|..82.|.90..|..730.|..738.|..810.|..6562.|..6570.|.6642.|.7290|A038487

k=10.|.11..|.101.|.110.|.1001.|.1010.|.1100.|.10001.|.10010.|10100.|11000|A038444

k=11.|.12..|.122.|.132.|.1332.|.1342.|.1452.|.14642.|.14652.|14762.|15972|A038490

k=12.|.13..|.145.|.156.|.1729.|.1740.|.1872.|.20737.|.20748.|20880.|22464|A038492

================================================================================

CROSSREFS

Cf. A002378, A002522, A018900, A038464, A038470, A038474, A038478, A038481, A038484, A038487, A038444, A038490, A038492.

Sequence in context: A181132 A278168 A130271 * A151555 A263728 A103606

Adjacent sequences:  A139366 A139367 A139368 * A139370 A139371 A139372

KEYWORD

easy,nonn,tabl

AUTHOR

Jonathan Vos Post, Jun 07 2008

STATUS

approved

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Last modified August 14 19:45 EDT 2020. Contains 336483 sequences. (Running on oeis4.)