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A225067 Least heptagonal (7-gonal) number that is the product of n heptagonal numbers greater than 1. 1
7, 6426, 35224, 2077992, 3610893055, 14209771072, 118896888880, 6400213601782, 22535310978496008, 22535310978496008, 2418562185097611420000, 2462278542548750181849600 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..12.

Lars Blomberg, Table of n, a(n) with solutions for n=1..12

EXAMPLE

Let hep(n) = n*(5n-3)/2. Then

a(1) = 7 = hep(2).

a(2) = 6426 = hep(51) = hep(4) * hep(9).

a(3) = 35224 = hep(119) = hep(2) * hep(4) * hep(8).

a(4) = 2077992 = hep(912) = hep(2)^2 * hep(3) * hep(31).

a(5) = 3610893055 = hep(38005) = hep(2)^3 * hep(5) * hep(277).

a(6) = 14209771072 = hep(75392) = hep(2)^4 * hep(31) * hep(32).

CROSSREFS

Cf. A000566 (heptagonal numbers).

Cf. A212616, A212617, A225066-A225070 (3-, 5- to 10-gonal cases).

Sequence in context: A125036 A098803 A246853 * A281358 A068575 A158400

Adjacent sequences:  A225064 A225065 A225066 * A225068 A225069 A225070

KEYWORD

nonn,more

AUTHOR

T. D. Noe, May 01 2013

EXTENSIONS

Corrected a(6) and added a(7)-a(12) by Lars Blomberg, Sep 21 2013

STATUS

approved

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Last modified October 23 14:54 EDT 2019. Contains 328345 sequences. (Running on oeis4.)